diff --git a/src/main/java/dan200/computercraft/client/gui/GuiComputer.java b/src/main/java/dan200/computercraft/client/gui/GuiComputer.java
index 4996be560..57755785a 100644
--- a/src/main/java/dan200/computercraft/client/gui/GuiComputer.java
+++ b/src/main/java/dan200/computercraft/client/gui/GuiComputer.java
@@ -7,8 +7,8 @@
 
 import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.gui.widgets.ComputerSidebar;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
-import dan200.computercraft.client.gui.widgets.WidgetWrapper;
 import dan200.computercraft.client.render.ComputerBorderRenderer;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
@@ -17,12 +17,12 @@
 import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
 import dan200.computercraft.shared.pocket.inventory.ContainerPocketComputer;
 import net.minecraft.client.gui.screen.inventory.ContainerScreen;
+import net.minecraft.client.gui.widget.Widget;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.util.text.ITextComponent;
 import org.lwjgl.glfw.GLFW;
 
 import static dan200.computercraft.client.render.ComputerBorderRenderer.BORDER;
-import static dan200.computercraft.client.render.ComputerBorderRenderer.MARGIN;
 
 public final class GuiComputer<T extends ContainerComputerBase> extends ContainerScreen<T>
 {
@@ -31,8 +31,7 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
     private final int termWidth;
     private final int termHeight;
 
-    private WidgetTerminal terminal;
-    private WidgetWrapper terminalWrapper;
+    private WidgetTerminal terminal = null;
 
     private GuiComputer(
         T container, PlayerInventory player, ITextComponent title, int termWidth, int termHeight
@@ -43,7 +42,9 @@ private GuiComputer(
         computer = (ClientComputer) container.getComputer();
         this.termWidth = termWidth;
         this.termHeight = termHeight;
-        terminal = null;
+
+        imageWidth = WidgetTerminal.getWidth( termWidth ) + BORDER * 2 + ComputerSidebar.WIDTH;
+        imageHeight = WidgetTerminal.getHeight( termHeight ) + BORDER * 2;
     }
 
     public static GuiComputer<ContainerComputer> create( ContainerComputer container, PlayerInventory inventory, ITextComponent component )
@@ -74,29 +75,21 @@ public static GuiComputer<ContainerViewComputer> createView( ContainerViewComput
     @Override
     protected void init()
     {
-        minecraft.keyboardHandler.setSendRepeatsToGui( true );
-
-        int termPxWidth = termWidth * FixedWidthFontRenderer.FONT_WIDTH;
-        int termPxHeight = termHeight * FixedWidthFontRenderer.FONT_HEIGHT;
-
-        imageWidth = termPxWidth + MARGIN * 2 + BORDER * 2;
-        imageHeight = termPxHeight + MARGIN * 2 + BORDER * 2;
-
         super.init();
 
-        terminal = new WidgetTerminal( minecraft, () -> computer, termWidth, termHeight, MARGIN, MARGIN, MARGIN, MARGIN );
-        terminalWrapper = new WidgetWrapper( terminal, MARGIN + BORDER + leftPos, MARGIN + BORDER + topPos, termPxWidth, termPxHeight );
+        minecraft.keyboardHandler.setSendRepeatsToGui( true );
 
-        children.add( terminalWrapper );
-        setFocused( terminalWrapper );
+        terminal = addButton( new WidgetTerminal( computer,
+            leftPos + ComputerSidebar.WIDTH + BORDER, topPos + BORDER, termWidth, termHeight
+        ) );
+        ComputerSidebar.addButtons( this, computer, this::addButton, leftPos, topPos + BORDER );
+        setFocused( terminal );
     }
 
     @Override
     public void removed()
     {
         super.removed();
-        children.remove( terminal );
-        terminal = null;
         minecraft.keyboardHandler.setSendRepeatsToGui( false );
     }
 
@@ -111,7 +104,7 @@ public void tick()
     public boolean keyPressed( int key, int scancode, int modifiers )
     {
         // Forward the tab key to the terminal, rather than moving between controls.
-        if( key == GLFW.GLFW_KEY_TAB && getFocused() != null && getFocused() == terminalWrapper )
+        if( key == GLFW.GLFW_KEY_TAB && getFocused() != null && getFocused() == terminal )
         {
             return getFocused().keyPressed( key, scancode, modifiers );
         }
@@ -122,16 +115,11 @@ public boolean keyPressed( int key, int scancode, int modifiers )
     @Override
     public void renderBg( float partialTicks, int mouseX, int mouseY )
     {
-        // Draw terminal
-        terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
-
         // Draw a border around the terminal
         RenderSystem.color4f( 1, 1, 1, 1 );
         minecraft.getTextureManager().bind( ComputerBorderRenderer.getTexture( family ) );
-        ComputerBorderRenderer.render(
-            terminalWrapper.getX() - MARGIN, terminalWrapper.getY() - MARGIN, getBlitOffset(),
-            terminalWrapper.getWidth() + MARGIN * 2, terminalWrapper.getHeight() + MARGIN * 2
-        );
+        ComputerBorderRenderer.render( terminal.x, terminal.y, getBlitOffset(), terminal.getWidth(), terminal.getHeight() );
+        ComputerSidebar.renderBackground( leftPos, topPos + BORDER );
     }
 
     @Override
@@ -140,6 +128,11 @@ public void render( int mouseX, int mouseY, float partialTicks )
         renderBackground();
         super.render( mouseX, mouseY, partialTicks );
         renderTooltip( mouseX, mouseY );
+
+        for( Widget widget : buttons )
+        {
+            if( widget.isHovered() ) widget.renderToolTip( mouseX, mouseY );
+        }
     }
 
     @Override
diff --git a/src/main/java/dan200/computercraft/client/gui/GuiTurtle.java b/src/main/java/dan200/computercraft/client/gui/GuiTurtle.java
index 6af2a5790..ff24c6da0 100644
--- a/src/main/java/dan200/computercraft/client/gui/GuiTurtle.java
+++ b/src/main/java/dan200/computercraft/client/gui/GuiTurtle.java
@@ -7,17 +7,21 @@
 
 import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.gui.widgets.ComputerSidebar;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
-import dan200.computercraft.client.gui.widgets.WidgetWrapper;
+import dan200.computercraft.client.render.ComputerBorderRenderer;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
 import net.minecraft.client.gui.screen.inventory.ContainerScreen;
+import net.minecraft.client.gui.widget.Widget;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.text.ITextComponent;
 import org.lwjgl.glfw.GLFW;
 
+import static dan200.computercraft.shared.turtle.inventory.ContainerTurtle.*;
+
 public class GuiTurtle extends ContainerScreen<ContainerTurtle>
 {
     private static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/turtle_normal.png" );
@@ -29,7 +33,6 @@ public class GuiTurtle extends ContainerScreen<ContainerTurtle>
     private final ClientComputer computer;
 
     private WidgetTerminal terminal;
-    private WidgetWrapper terminalWrapper;
 
     public GuiTurtle( ContainerTurtle container, PlayerInventory player, ITextComponent title )
     {
@@ -49,27 +52,18 @@ protected void init()
         super.init();
         minecraft.keyboardHandler.setSendRepeatsToGui( true );
 
-        int termPxWidth = ComputerCraft.turtleTermWidth * FixedWidthFontRenderer.FONT_WIDTH;
-        int termPxHeight = ComputerCraft.turtleTermHeight * FixedWidthFontRenderer.FONT_HEIGHT;
-
-        terminal = new WidgetTerminal(
-            minecraft, () -> computer,
-            ComputerCraft.turtleTermWidth,
-            ComputerCraft.turtleTermHeight,
-            2, 2, 2, 2
-        );
-        terminalWrapper = new WidgetWrapper( terminal, 2 + 8 + leftPos, 2 + 8 + topPos, termPxWidth, termPxHeight );
-
-        children.add( terminalWrapper );
-        setFocused( terminalWrapper );
+        terminal = addButton( new WidgetTerminal(
+            computer, leftPos + BORDER + ComputerSidebar.WIDTH, topPos + BORDER,
+            ComputerCraft.turtleTermWidth, ComputerCraft.turtleTermHeight
+        ) );
+        ComputerSidebar.addButtons( this, computer, this::addButton, leftPos, topPos + BORDER );
+        setFocused( terminal );
     }
 
     @Override
     public void removed()
     {
         super.removed();
-        children.remove( terminal );
-        terminal = null;
         minecraft.keyboardHandler.setSendRepeatsToGui( false );
     }
 
@@ -84,7 +78,7 @@ public void tick()
     public boolean keyPressed( int key, int scancode, int modifiers )
     {
         // Forward the tab key to the terminal, rather than moving between controls.
-        if( key == GLFW.GLFW_KEY_TAB && getFocused() != null && getFocused() == terminalWrapper )
+        if( key == GLFW.GLFW_KEY_TAB && getFocused() != null && getFocused() == terminal )
         {
             return getFocused().keyPressed( key, scancode, modifiers );
         }
@@ -92,41 +86,42 @@ public boolean keyPressed( int key, int scancode, int modifiers )
         return super.keyPressed( key, scancode, modifiers );
     }
 
-    private void drawSelectionSlot( boolean advanced )
+    @Override
+    protected void renderBg( float partialTicks, int mouseX, int mouseY )
     {
-        // Draw selection slot
+        boolean advanced = family == ComputerFamily.ADVANCED;
+
+        RenderSystem.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
+        minecraft.getTextureManager().bind( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
+        blit( leftPos + ComputerSidebar.WIDTH, topPos, 0, 0, imageWidth, imageHeight );
+
+        minecraft.getTextureManager().bind( advanced ? ComputerBorderRenderer.BACKGROUND_ADVANCED : ComputerBorderRenderer.BACKGROUND_NORMAL );
+        ComputerSidebar.renderBackground( leftPos, topPos + BORDER );
+
         int slot = container.getSelectedSlot();
         if( slot >= 0 )
         {
             RenderSystem.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
             int slotX = slot % 4;
             int slotY = slot / 4;
-            minecraft.getTextureManager().bind( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-            blit( leftPos + ContainerTurtle.TURTLE_START_X - 2 + slotX * 18, topPos + ContainerTurtle.PLAYER_START_Y - 2 + slotY * 18, 0, 217, 24, 24 );
+            blit(
+                leftPos + TURTLE_START_X - 2 + slotX * 18, topPos + PLAYER_START_Y - 2 + slotY * 18,
+                0, 217, 24, 24
+            );
         }
     }
 
-    @Override
-    protected void renderBg( float partialTicks, int mouseX, int mouseY )
-    {
-        // Draw term
-        boolean advanced = family == ComputerFamily.ADVANCED;
-        terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
-
-        // Draw border/inventory
-        RenderSystem.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
-        minecraft.getTextureManager().bind( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-        blit( leftPos, topPos, 0, 0, imageWidth, imageHeight );
-
-        drawSelectionSlot( advanced );
-    }
-
     @Override
     public void render( int mouseX, int mouseY, float partialTicks )
     {
         renderBackground();
         super.render( mouseX, mouseY, partialTicks );
         renderTooltip( mouseX, mouseY );
+
+        for( Widget widget : buttons )
+        {
+            if( widget.isHovered() ) widget.renderToolTip( mouseX, mouseY );
+        }
     }
 
     @Override
diff --git a/src/main/java/dan200/computercraft/client/gui/widgets/ComputerSidebar.java b/src/main/java/dan200/computercraft/client/gui/widgets/ComputerSidebar.java
new file mode 100644
index 000000000..65cf1ae8a
--- /dev/null
+++ b/src/main/java/dan200/computercraft/client/gui/widgets/ComputerSidebar.java
@@ -0,0 +1,105 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.client.gui.widgets;
+
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.render.ComputerBorderRenderer;
+import dan200.computercraft.shared.computer.core.ClientComputer;
+import net.minecraft.client.gui.screen.Screen;
+import net.minecraft.client.gui.widget.Widget;
+import net.minecraft.client.resources.I18n;
+import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.text.TextFormatting;
+
+import java.util.Arrays;
+import java.util.function.Consumer;
+
+/**
+ * Registers buttons to interact with a computer.
+ */
+public final class ComputerSidebar
+{
+    private static final ResourceLocation TEXTURE = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/buttons.png" );
+
+    private static final int TEX_SIZE = 64;
+
+    private static final int ICON_WIDTH = 12;
+    private static final int ICON_HEIGHT = 12;
+    private static final int ICON_MARGIN = 2;
+
+    private static final int ICON_TEX_Y_DIFF = 14;
+
+    private static final int CORNERS_BORDER = 3;
+    private static final int FULL_BORDER = CORNERS_BORDER + ICON_MARGIN;
+
+    private static final int BUTTONS = 2;
+    private static final int HEIGHT = (ICON_HEIGHT + ICON_MARGIN * 2) * BUTTONS + CORNERS_BORDER * 2;
+    public static final int WIDTH = 17;
+
+    private ComputerSidebar()
+    {
+    }
+
+    public static void addButtons( Screen screen, ClientComputer computer, Consumer<Widget> add, int x, int y )
+    {
+        x += CORNERS_BORDER + 1;
+        y += CORNERS_BORDER + ICON_MARGIN;
+
+        add.accept( new DynamicImageButton(
+            screen, x, y, ICON_WIDTH, ICON_HEIGHT, () -> computer.isOn() ? 15 : 1, 1, ICON_TEX_Y_DIFF,
+            TEXTURE, TEX_SIZE, TEX_SIZE, b -> toggleComputer( computer ),
+            () -> computer.isOn() ? Arrays.asList(
+                I18n.get( "gui.computercraft.tooltip.turn_off" ),
+                TextFormatting.GRAY + I18n.get( "gui.computercraft.tooltip.turn_off.key" )
+            ) : Arrays.asList(
+                I18n.get( "gui.computercraft.tooltip.turn_on" ),
+                TextFormatting.GRAY + I18n.get( "gui.computercraft.tooltip.turn_off.key" )
+            )
+        ) );
+
+        y += ICON_HEIGHT + ICON_MARGIN * 2;
+
+        add.accept( new DynamicImageButton(
+            screen, x, y, ICON_WIDTH, ICON_HEIGHT, 29, 1, ICON_TEX_Y_DIFF,
+            TEXTURE, TEX_SIZE, TEX_SIZE, b -> computer.queueEvent( "terminate" ),
+            Arrays.asList(
+                I18n.get( "gui.computercraft.tooltip.terminate" ),
+                TextFormatting.GRAY + I18n.get( "gui.computercraft.tooltip.terminate.key" )
+            )
+        ) );
+    }
+
+    public static void renderBackground( int x, int y )
+    {
+        Screen.blit(
+            x, y, 0, 102, WIDTH, FULL_BORDER,
+            ComputerBorderRenderer.TEX_SIZE, ComputerBorderRenderer.TEX_SIZE
+        );
+
+        Screen.blit(
+            x, y + FULL_BORDER, WIDTH, HEIGHT - FULL_BORDER * 2,
+            0, 107, WIDTH, 4,
+            ComputerBorderRenderer.TEX_SIZE, ComputerBorderRenderer.TEX_SIZE
+        );
+
+        Screen.blit(
+            x, y + HEIGHT - FULL_BORDER, 0, 111, WIDTH, FULL_BORDER,
+            ComputerBorderRenderer.TEX_SIZE, ComputerBorderRenderer.TEX_SIZE
+        );
+    }
+
+    private static void toggleComputer( ClientComputer computer )
+    {
+        if( computer.isOn() )
+        {
+            computer.shutdown();
+        }
+        else
+        {
+            computer.turnOn();
+        }
+    }
+}
diff --git a/src/main/java/dan200/computercraft/client/gui/widgets/DynamicImageButton.java b/src/main/java/dan200/computercraft/client/gui/widgets/DynamicImageButton.java
new file mode 100644
index 000000000..af21d9e93
--- /dev/null
+++ b/src/main/java/dan200/computercraft/client/gui/widgets/DynamicImageButton.java
@@ -0,0 +1,92 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.client.gui.widgets;
+
+import com.mojang.blaze3d.systems.RenderSystem;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.screen.Screen;
+import net.minecraft.client.gui.widget.button.Button;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.common.util.NonNullSupplier;
+
+import javax.annotation.Nonnull;
+import java.util.List;
+import java.util.function.IntSupplier;
+
+/**
+ * Version of {@link net.minecraft.client.gui.widget.button.ImageButton} which allows changing some properties
+ * dynamically.
+ */
+public class DynamicImageButton extends Button
+{
+    private final Screen screen;
+    private final ResourceLocation texture;
+    private final IntSupplier xTexStart;
+    private final int yTexStart;
+    private final int yDiffTex;
+    private final int textureWidth;
+    private final int textureHeight;
+    private final NonNullSupplier<List<String>> tooltip;
+
+    public DynamicImageButton(
+        Screen screen, int x, int y, int width, int height, int xTexStart, int yTexStart, int yDiffTex,
+        ResourceLocation texture, int textureWidth, int textureHeight,
+        IPressable onPress, List<String> tooltip
+    )
+    {
+        this(
+            screen, x, y, width, height, () -> xTexStart, yTexStart, yDiffTex,
+            texture, textureWidth, textureHeight,
+            onPress, () -> tooltip
+        );
+    }
+
+
+    public DynamicImageButton(
+        Screen screen, int x, int y, int width, int height, IntSupplier xTexStart, int yTexStart, int yDiffTex,
+        ResourceLocation texture, int textureWidth, int textureHeight,
+        IPressable onPress, NonNullSupplier<List<String>> tooltip
+    )
+    {
+        super( x, y, width, height, "", onPress );
+        this.screen = screen;
+        this.textureWidth = textureWidth;
+        this.textureHeight = textureHeight;
+        this.xTexStart = xTexStart;
+        this.yTexStart = yTexStart;
+        this.yDiffTex = yDiffTex;
+        this.texture = texture;
+        this.tooltip = tooltip;
+    }
+
+    public void renderButton( int mouseX, int mouseY, float partialTicks )
+    {
+        Minecraft minecraft = Minecraft.getInstance();
+        minecraft.getTextureManager().bind( texture );
+        RenderSystem.disableDepthTest();
+
+        int yTex = yTexStart;
+        if( isHovered() ) yTex += yDiffTex;
+
+        blit( x, y, xTexStart.getAsInt(), yTex, width, height, textureWidth, textureHeight );
+        RenderSystem.enableDepthTest();
+    }
+
+    @Nonnull
+    @Override
+    public String getMessage()
+    {
+        List<String> tooltip = this.tooltip.get();
+        return tooltip.isEmpty() ? "" : tooltip.get( 0 );
+    }
+
+    @Override
+    public void renderToolTip( int mouseX, int mouseY )
+    {
+        List<String> tooltip = this.tooltip.get();
+        if( !tooltip.isEmpty() ) screen.renderTooltip( tooltip, mouseX, mouseY );
+    }
+}
diff --git a/src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java b/src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java
index 343e5229e..747654545 100644
--- a/src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java
+++ b/src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java
@@ -8,29 +8,29 @@
 import dan200.computercraft.client.gui.FixedWidthFontRenderer;
 import dan200.computercraft.core.terminal.Terminal;
 import dan200.computercraft.shared.computer.core.ClientComputer;
-import dan200.computercraft.shared.computer.core.IComputer;
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.gui.IGuiEventListener;
+import net.minecraft.client.gui.widget.Widget;
 import net.minecraft.util.SharedConstants;
 import org.lwjgl.glfw.GLFW;
 
+import javax.annotation.Nonnull;
 import java.util.BitSet;
-import java.util.function.Supplier;
 
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_WIDTH;
+import static dan200.computercraft.client.render.ComputerBorderRenderer.MARGIN;
 
-public class WidgetTerminal implements IGuiEventListener
+public class WidgetTerminal extends Widget
 {
     private static final float TERMINATE_TIME = 0.5f;
 
-    private final Minecraft client;
+    private final ClientComputer computer;
 
-    private boolean focused;
-
-    private final Supplier<ClientComputer> computer;
-    private final int termWidth;
-    private final int termHeight;
+    // The positions of the actual terminal
+    private final int innerX;
+    private final int innerY;
+    private final int innerWidth;
+    private final int innerHeight;
 
     private float terminateTimer = -1;
     private float rebootTimer = -1;
@@ -40,23 +40,18 @@ public class WidgetTerminal implements IGuiEventListener
     private int lastMouseX = -1;
     private int lastMouseY = -1;
 
-    private final int leftMargin;
-    private final int rightMargin;
-    private final int topMargin;
-    private final int bottomMargin;
-
     private final BitSet keysDown = new BitSet( 256 );
 
-    public WidgetTerminal( Minecraft client, Supplier<ClientComputer> computer, int termWidth, int termHeight, int leftMargin, int rightMargin, int topMargin, int bottomMargin )
+    public WidgetTerminal( @Nonnull ClientComputer computer, int x, int y, int termWidth, int termHeight )
     {
-        this.client = client;
+        super( x, y, termWidth * FONT_WIDTH + MARGIN * 2, termHeight * FONT_HEIGHT + MARGIN * 2, "" );
+
         this.computer = computer;
-        this.termWidth = termWidth;
-        this.termHeight = termHeight;
-        this.leftMargin = leftMargin;
-        this.rightMargin = rightMargin;
-        this.topMargin = topMargin;
-        this.bottomMargin = bottomMargin;
+
+        innerX = x + MARGIN;
+        innerY = y + MARGIN;
+        innerWidth = termWidth * FONT_WIDTH;
+        innerHeight = termHeight * FONT_HEIGHT;
     }
 
     @Override
@@ -65,7 +60,7 @@ public boolean charTyped( char ch, int modifiers )
         if( ch >= 32 && ch <= 126 || ch >= 160 && ch <= 255 ) // printable chars in byte range
         {
             // Queue the "char" event
-            queueEvent( "char", Character.toString( ch ) );
+            computer.queueEvent( "char", new Object[] { Character.toString( ch ) } );
         }
 
         return true;
@@ -91,7 +86,7 @@ public boolean keyPressed( int key, int scancode, int modifiers )
 
                 case GLFW.GLFW_KEY_V:
                     // Ctrl+V for paste
-                    String clipboard = client.keyboardHandler.getClipboard();
+                    String clipboard = Minecraft.getInstance().keyboardHandler.getClipboard();
                     if( clipboard != null )
                     {
                         // Clip to the first occurrence of \r or \n
@@ -116,7 +111,7 @@ else if( newLineIndex2 >= 0 )
                         {
                             // Clip to 512 characters and queue the event
                             if( clipboard.length() > 512 ) clipboard = clipboard.substring( 0, 512 );
-                            queueEvent( "paste", clipboard );
+                            computer.queueEvent( "paste", new Object[] { clipboard } );
                         }
 
                         return true;
@@ -129,8 +124,7 @@ else if( newLineIndex2 >= 0 )
             // Queue the "key" event and add to the down set
             boolean repeat = keysDown.get( key );
             keysDown.set( key );
-            IComputer computer = this.computer.get();
-            if( computer != null ) computer.keyDown( key, repeat );
+            computer.keyDown( key, repeat );
         }
 
         return true;
@@ -143,8 +137,7 @@ public boolean keyReleased( int key, int scancode, int modifiers )
         if( key >= 0 && keysDown.get( key ) )
         {
             keysDown.set( key, false );
-            IComputer computer = this.computer.get();
-            if( computer != null ) computer.keyUp( key );
+            computer.keyUp( key );
         }
 
         switch( key )
@@ -170,14 +163,14 @@ public boolean keyReleased( int key, int scancode, int modifiers )
     @Override
     public boolean mouseClicked( double mouseX, double mouseY, int button )
     {
-        ClientComputer computer = this.computer.get();
-        if( computer == null || !computer.isColour() || button < 0 || button > 2 ) return false;
+        if( !inTermRegion( mouseX, mouseY ) ) return false;
+        if( !computer.isColour() || button < 0 || button > 2 ) return false;
 
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FONT_WIDTH);
-            int charY = (int) (mouseY / FONT_HEIGHT);
+            int charX = (int) ((mouseX - x) / FONT_WIDTH);
+            int charY = (int) ((mouseY - x) / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -194,14 +187,14 @@ public boolean mouseClicked( double mouseX, double mouseY, int button )
     @Override
     public boolean mouseReleased( double mouseX, double mouseY, int button )
     {
-        ClientComputer computer = this.computer.get();
-        if( computer == null || !computer.isColour() || button < 0 || button > 2 ) return false;
+        if( !inTermRegion( mouseX, mouseY ) ) return false;
+        if( !computer.isColour() || button < 0 || button > 2 ) return false;
 
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FONT_WIDTH);
-            int charY = (int) (mouseY / FONT_HEIGHT);
+            int charX = (int) ((mouseX - x) / FONT_WIDTH);
+            int charY = (int) ((mouseY - x) / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -221,14 +214,14 @@ public boolean mouseReleased( double mouseX, double mouseY, int button )
     @Override
     public boolean mouseDragged( double mouseX, double mouseY, int button, double v2, double v3 )
     {
-        ClientComputer computer = this.computer.get();
-        if( computer == null || !computer.isColour() || button < 0 || button > 2 ) return false;
+        if( !inTermRegion( mouseX, mouseY ) ) return false;
+        if( !computer.isColour() || button < 0 || button > 2 ) return false;
 
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FONT_WIDTH);
-            int charY = (int) (mouseY / FONT_HEIGHT);
+            int charX = (int) ((mouseX - x) / FONT_WIDTH);
+            int charY = (int) ((mouseY - x) / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -246,14 +239,14 @@ public boolean mouseDragged( double mouseX, double mouseY, int button, double v2
     @Override
     public boolean mouseScrolled( double mouseX, double mouseY, double delta )
     {
-        ClientComputer computer = this.computer.get();
-        if( computer == null || !computer.isColour() || delta == 0 ) return false;
+        if( !inTermRegion( mouseX, mouseY ) ) return false;
+        if( !computer.isColour() || delta == 0 ) return false;
 
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FONT_WIDTH);
-            int charY = (int) (mouseY / FONT_HEIGHT);
+            int charX = (int) ((mouseX - innerX) / FONT_WIDTH);
+            int charY = (int) ((mouseY - innerY) / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -266,84 +259,64 @@ public boolean mouseScrolled( double mouseX, double mouseY, double delta )
         return true;
     }
 
+    private boolean inTermRegion( double mouseX, double mouseY )
+    {
+        return active && visible && mouseX >= innerX && mouseY >= innerY && mouseX < innerX + innerWidth && mouseY < innerY + innerHeight;
+    }
+
     public void update()
     {
         if( terminateTimer >= 0 && terminateTimer < TERMINATE_TIME && (terminateTimer += 0.05f) > TERMINATE_TIME )
         {
-            queueEvent( "terminate" );
+            computer.queueEvent( "terminate" );
         }
 
         if( shutdownTimer >= 0 && shutdownTimer < TERMINATE_TIME && (shutdownTimer += 0.05f) > TERMINATE_TIME )
         {
-            ClientComputer computer = this.computer.get();
-            if( computer != null ) computer.shutdown();
+            computer.shutdown();
         }
 
         if( rebootTimer >= 0 && rebootTimer < TERMINATE_TIME && (rebootTimer += 0.05f) > TERMINATE_TIME )
         {
-            ClientComputer computer = this.computer.get();
-            if( computer != null ) computer.reboot();
+            computer.reboot();
         }
     }
 
     @Override
-    public boolean changeFocus( boolean reversed )
+    public void onFocusedChanged( boolean focused )
     {
-        if( focused )
+        if( !focused )
         {
             // When blurring, we should make all keys go up
             for( int key = 0; key < keysDown.size(); key++ )
             {
-                if( keysDown.get( key ) ) queueEvent( "key_up", key );
+                if( keysDown.get( key ) ) computer.keyUp( key );
             }
             keysDown.clear();
 
             // When blurring, we should make the last mouse button go up
             if( lastMouseButton > 0 )
             {
-                IComputer computer = this.computer.get();
-                if( computer != null ) computer.mouseUp( lastMouseButton + 1, lastMouseX + 1, lastMouseY + 1 );
+                computer.mouseUp( lastMouseButton + 1, lastMouseX + 1, lastMouseY + 1 );
                 lastMouseButton = -1;
             }
 
             shutdownTimer = terminateTimer = rebootTimer = -1;
         }
-        focused = !focused;
-        return true;
     }
 
-    public void draw( int originX, int originY )
+    public void render( int mouseX, int mouseY, float partialTicks )
     {
-        synchronized( computer )
+        // Draw the screen contents
+        Terminal terminal = computer.getTerminal();
+        if( terminal != null )
         {
-            // Draw the screen contents
-            ClientComputer computer = this.computer.get();
-            Terminal terminal = computer != null ? computer.getTerminal() : null;
-            if( terminal != null )
-            {
-                FixedWidthFontRenderer.drawTerminal( originX, originY, terminal, !computer.isColour(), topMargin, bottomMargin, leftMargin, rightMargin );
-            }
-            else
-            {
-                FixedWidthFontRenderer.drawEmptyTerminal(
-                    originX - leftMargin, originY - rightMargin,
-                    termWidth * FONT_WIDTH + leftMargin + rightMargin,
-                    termHeight * FONT_HEIGHT + topMargin + bottomMargin
-                );
-            }
+            FixedWidthFontRenderer.drawTerminal( innerX, innerY, terminal, !computer.isColour(), MARGIN, MARGIN, MARGIN, MARGIN );
+        }
+        else
+        {
+            FixedWidthFontRenderer.drawEmptyTerminal( x, y, width, height );
         }
-    }
-
-    private void queueEvent( String event )
-    {
-        ClientComputer computer = this.computer.get();
-        if( computer != null ) computer.queueEvent( event );
-    }
-
-    private void queueEvent( String event, Object... args )
-    {
-        ClientComputer computer = this.computer.get();
-        if( computer != null ) computer.queueEvent( event, args );
     }
 
     @Override
@@ -351,4 +324,14 @@ public boolean isMouseOver( double x, double y )
     {
         return true;
     }
+
+    public static int getWidth( int termWidth )
+    {
+        return termWidth * FONT_WIDTH + MARGIN * 2;
+    }
+
+    public static int getHeight( int termHeight )
+    {
+        return termHeight * FONT_HEIGHT + MARGIN * 2;
+    }
 }
diff --git a/src/main/java/dan200/computercraft/client/gui/widgets/WidgetWrapper.java b/src/main/java/dan200/computercraft/client/gui/widgets/WidgetWrapper.java
deleted file mode 100644
index 45ca4617e..000000000
--- a/src/main/java/dan200/computercraft/client/gui/widgets/WidgetWrapper.java
+++ /dev/null
@@ -1,105 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.client.gui.widgets;
-
-import net.minecraft.client.gui.IGuiEventListener;
-
-public class WidgetWrapper implements IGuiEventListener
-{
-    private final IGuiEventListener listener;
-    private final int x;
-    private final int y;
-    private final int width;
-    private final int height;
-
-    public WidgetWrapper( IGuiEventListener listener, int x, int y, int width, int height )
-    {
-        this.listener = listener;
-        this.x = x;
-        this.y = y;
-        this.width = width;
-        this.height = height;
-    }
-
-    @Override
-    public boolean changeFocus( boolean b )
-    {
-        return listener.changeFocus( b );
-    }
-
-    @Override
-    public boolean mouseClicked( double x, double y, int button )
-    {
-        double dx = x - this.x, dy = y - this.y;
-        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseClicked( dx, dy, button );
-    }
-
-    @Override
-    public boolean mouseReleased( double x, double y, int button )
-    {
-        double dx = x - this.x, dy = y - this.y;
-        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseReleased( dx, dy, button );
-    }
-
-    @Override
-    public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
-    {
-        double dx = x - this.x, dy = y - this.y;
-        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseDragged( dx, dy, button, deltaX, deltaY );
-    }
-
-    @Override
-    public boolean mouseScrolled( double x, double y, double delta )
-    {
-        double dx = x - this.x, dy = y - this.y;
-        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseScrolled( dx, dy, delta );
-    }
-
-    @Override
-    public boolean keyPressed( int key, int scancode, int modifiers )
-    {
-        return listener.keyPressed( key, scancode, modifiers );
-    }
-
-    @Override
-    public boolean keyReleased( int key, int scancode, int modifiers )
-    {
-        return listener.keyReleased( key, scancode, modifiers );
-    }
-
-    @Override
-    public boolean charTyped( char character, int modifiers )
-    {
-        return listener.charTyped( character, modifiers );
-    }
-
-    public int getX()
-    {
-        return x;
-    }
-
-    public int getY()
-    {
-        return y;
-    }
-
-    public int getWidth()
-    {
-        return width;
-    }
-
-    public int getHeight()
-    {
-        return height;
-    }
-
-    @Override
-    public boolean isMouseOver( double x, double y )
-    {
-        double dx = x - this.x, dy = y - this.y;
-        return dx >= 0 && dx < width && dy >= 0 && dy < height;
-    }
-}
diff --git a/src/main/java/dan200/computercraft/client/render/ComputerBorderRenderer.java b/src/main/java/dan200/computercraft/client/render/ComputerBorderRenderer.java
index bd52458f3..bd6c047c6 100644
--- a/src/main/java/dan200/computercraft/client/render/ComputerBorderRenderer.java
+++ b/src/main/java/dan200/computercraft/client/render/ComputerBorderRenderer.java
@@ -52,7 +52,8 @@ public class ComputerBorderRenderer
 
     public static final int LIGHT_HEIGHT = 8;
 
-    private static final float TEX_SCALE = 1 / 256.0f;
+    public static final int TEX_SIZE = 256;
+    private static final float TEX_SCALE = 1 / (float) TEX_SIZE;
 
     private final Matrix4f transform;
     private final IVertexBuilder builder;
diff --git a/src/main/java/dan200/computercraft/shared/turtle/inventory/ContainerTurtle.java b/src/main/java/dan200/computercraft/shared/turtle/inventory/ContainerTurtle.java
index c11357614..fffa5ea26 100644
--- a/src/main/java/dan200/computercraft/shared/turtle/inventory/ContainerTurtle.java
+++ b/src/main/java/dan200/computercraft/shared/turtle/inventory/ContainerTurtle.java
@@ -5,6 +5,7 @@
  */
 package dan200.computercraft.shared.turtle.inventory;
 
+import dan200.computercraft.client.gui.widgets.ComputerSidebar;
 import dan200.computercraft.shared.Registry;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.IComputer;
@@ -27,8 +28,10 @@
 
 public class ContainerTurtle extends ContainerComputerBase
 {
+    public static final int BORDER = 8;
     public static final int PLAYER_START_Y = 134;
-    public static final int TURTLE_START_X = 175;
+    public static final int TURTLE_START_X = ComputerSidebar.WIDTH + 175;
+    public static final int PLAYER_START_X = ComputerSidebar.WIDTH + BORDER;
 
     private final IIntArray properties;
 
@@ -56,14 +59,14 @@ private ContainerTurtle(
         {
             for( int x = 0; x < 9; x++ )
             {
-                addSlot( new Slot( playerInventory, x + y * 9 + 9, 8 + x * 18, PLAYER_START_Y + 1 + y * 18 ) );
+                addSlot( new Slot( playerInventory, x + y * 9 + 9, PLAYER_START_X + x * 18, PLAYER_START_Y + 1 + y * 18 ) );
             }
         }
 
         // Player hotbar
         for( int x = 0; x < 9; x++ )
         {
-            addSlot( new Slot( playerInventory, x, 8 + x * 18, PLAYER_START_Y + 3 * 18 + 5 ) );
+            addSlot( new Slot( playerInventory, x, PLAYER_START_X + x * 18, PLAYER_START_Y + 3 * 18 + 5 ) );
         }
     }
 
diff --git a/src/main/resources/assets/computercraft/lang/en_us.json b/src/main/resources/assets/computercraft/lang/en_us.json
index f97fc40d7..755148279 100644
--- a/src/main/resources/assets/computercraft/lang/en_us.json
+++ b/src/main/resources/assets/computercraft/lang/en_us.json
@@ -110,5 +110,11 @@
     "tracking_field.computercraft.coroutines_dead.name": "Coroutines disposed",
     "gui.computercraft.tooltip.copy": "Copy to clipboard",
     "gui.computercraft.tooltip.computer_id": "Computer ID: %s",
-    "gui.computercraft.tooltip.disk_id": "Disk ID: %s"
+    "gui.computercraft.tooltip.disk_id": "Disk ID: %s",
+    "gui.computercraft.tooltip.turn_on": "Turn this computer on",
+    "gui.computercraft.tooltip.turn_on.key": "Hold Ctrl+R",
+    "gui.computercraft.tooltip.turn_off": "Turn this computer off",
+    "gui.computercraft.tooltip.turn_off.key": "Hold Ctrl+S",
+    "gui.computercraft.tooltip.terminate": "Stop the currently running code",
+    "gui.computercraft.tooltip.terminate.key": "Hold Ctrl+T"
 }
diff --git a/src/main/resources/assets/computercraft/textures/gui/buttons.png b/src/main/resources/assets/computercraft/textures/gui/buttons.png
new file mode 100644
index 000000000..69ef550ee
Binary files /dev/null and b/src/main/resources/assets/computercraft/textures/gui/buttons.png differ
diff --git a/src/main/resources/assets/computercraft/textures/gui/corners_advanced.png b/src/main/resources/assets/computercraft/textures/gui/corners_advanced.png
index d42b9e4fd..a53ae0715 100644
Binary files a/src/main/resources/assets/computercraft/textures/gui/corners_advanced.png and b/src/main/resources/assets/computercraft/textures/gui/corners_advanced.png differ
diff --git a/src/main/resources/assets/computercraft/textures/gui/corners_normal.png b/src/main/resources/assets/computercraft/textures/gui/corners_normal.png
index 8b1e9f676..0532a5289 100644
Binary files a/src/main/resources/assets/computercraft/textures/gui/corners_normal.png and b/src/main/resources/assets/computercraft/textures/gui/corners_normal.png differ