diff --git a/Shared/SpiderScene.cs b/Shared/SpiderScene.cs
new file mode 100644
index 0000000..2ba14e8
--- /dev/null
+++ b/Shared/SpiderScene.cs
@@ -0,0 +1,96 @@
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+using System;
+using System.Collections.Generic;
+
+namespace SemiColinGames {
+  public sealed class SpiderScene : IScene {
+
+    const float DESIRED_ASPECT_RATIO = 1920.0f / 1080.0f;
+
+    private readonly Color letterboxColor = Color.Blue;
+    private readonly Color backgroundColor = Color.Black;
+
+    private readonly GraphicsDevice graphics;
+    private readonly RenderTarget2D sceneTarget;
+    private readonly SpriteBatch spriteBatch;
+    private readonly BasicEffect basicEffect;
+
+    public SpiderScene(GraphicsDevice graphics, Point worldSize) {
+      this.graphics = graphics;
+
+      sceneTarget = new RenderTarget2D(
+        graphics, worldSize.X, worldSize.Y, false /* mipmap */,
+        graphics.PresentationParameters.BackBufferFormat, DepthFormat.Depth24);
+      spriteBatch = new SpriteBatch(graphics);
+
+      basicEffect = new BasicEffect(graphics) {
+        World = Matrix.CreateTranslation(0, 0, 0),
+        View = Matrix.CreateLookAt(Vector3.Backward, Vector3.Zero, Vector3.Up),
+        VertexColorEnabled = true
+      };
+    }
+
+    ~SpiderScene() {
+      Dispose();
+    }
+
+    public void Dispose() {
+      sceneTarget.Dispose();
+      spriteBatch.Dispose();
+      basicEffect.Dispose();
+      GC.SuppressFinalize(this);
+    }
+
+    public void Draw(bool isRunningSlowly, IWorld iworld, bool paused) {
+      SpiderWorld world = (SpiderWorld) iworld;
+
+      // Draw scene to sceneTarget.
+      graphics.SetRenderTarget(sceneTarget);
+      graphics.Clear(backgroundColor);
+
+      spriteBatch.Begin(SpriteSortMode.Deferred, BlendState.AlphaBlend,
+          SamplerState.PointClamp, DepthStencilState.Default,
+          RasterizerState.CullNone);
+
+      foreach (SpiderWorld.Anchor anchor in world.Anchors) {
+        anchor.Draw(spriteBatch);
+      }
+
+      world.Player.Draw(spriteBatch);
+
+      // Finish drawing sprites.
+      spriteBatch.End();
+
+      // Get ready to draw sceneTarget to screen.
+      graphics.SetRenderTarget(null);
+      graphics.Clear(letterboxColor);
+
+      // Letterbox the scene if needed.
+      float aspectRatio = 1.0f * graphics.Viewport.Width / graphics.Viewport.Height;
+      Rectangle drawRect;
+      if (aspectRatio > DESIRED_ASPECT_RATIO) {
+        // Need to letterbox the sides.
+        int desiredWidth = (int) (graphics.Viewport.Height * DESIRED_ASPECT_RATIO);
+        int padding = (graphics.Viewport.Width - desiredWidth) / 2;
+        drawRect = new Rectangle(padding, 0, desiredWidth, graphics.Viewport.Height);
+      } else {
+        // Need to letterbox the top / bottom.
+        int desiredHeight = (int) (graphics.Viewport.Width / DESIRED_ASPECT_RATIO);
+        int padding = (graphics.Viewport.Height - desiredHeight) / 2;
+        drawRect = new Rectangle(0, padding, graphics.Viewport.Width, desiredHeight);
+      }
+
+      // Actually draw to screen.
+      spriteBatch.Begin(SpriteSortMode.Deferred, BlendState.AlphaBlend,
+          SamplerState.PointClamp, DepthStencilState.Default,
+          RasterizerState.CullNone);
+      spriteBatch.Draw(sceneTarget, drawRect, Color.White);
+
+      // Draw debug toasts.
+      Debug.DrawToasts(spriteBatch);
+
+      spriteBatch.End();
+    }
+  }
+}
diff --git a/Shared/SpiderWorld.cs b/Shared/SpiderWorld.cs
new file mode 100644
index 0000000..b43e88c
--- /dev/null
+++ b/Shared/SpiderWorld.cs
@@ -0,0 +1,83 @@
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+using System;
+using System.Collections.Generic;
+
+namespace SemiColinGames {
+  public sealed class SpiderWorld : IWorld {
+
+    public class Spider {
+      public TextureRef Texture = Textures.Yellow2;
+      public Vector2 Position;
+      private Vector2 anchor;
+      private float radius;
+      private float angle;
+      private float momentum = -400;  // radians / second * pixels
+
+      public Spider(float x, float y, float radius, float angle) {
+        Position = new Vector2();
+        anchor = new Vector2(x, y);
+        this.angle = angle;
+        this.radius = radius;
+      }
+
+      public void Update(float modelTime, History<Input> input) {
+        radius += 100 * modelTime * input[0].Motion.Y;
+        radius = Math.Clamp(radius, 10, 300);
+        float angleChange = modelTime * momentum / radius;
+        angle += angleChange;
+        float x = anchor.X + radius * (float) Math.Sin(angle);
+        float y = anchor.Y + radius * (float) Math.Cos(angle);
+        Position.X = x;
+        Position.Y = y;
+      }
+
+      public void Draw(SpriteBatch spriteBatch) {
+        Texture2D texture = Texture.Get;
+        Vector2 spriteCenter = new Vector2(texture.Width / 2, texture.Height / 2);
+        Vector2 drawPos = Vector2.Floor(Vector2.Subtract(Position, spriteCenter));
+        spriteBatch.Draw(texture, drawPos, Color.White);
+      }
+    }
+
+    public class Anchor {
+      public TextureRef Texture = Textures.Blue1;
+      public Vector2 Position;
+
+      public Anchor(float x, float y) {
+        Position = new Vector2(x, y);
+      }
+
+      public void Draw(SpriteBatch spriteBatch) {
+        Texture2D texture = Texture.Get;
+        Vector2 spriteCenter = new Vector2(texture.Width / 2, texture.Height / 2);
+        Vector2 drawPos = Vector2.Floor(Vector2.Subtract(Position, spriteCenter));
+        spriteBatch.Draw(texture, drawPos, Color.White);
+      }
+    }
+
+    public readonly Rectangle Bounds;
+    public Spider Player;
+    public ProfilingList<Anchor> Anchors;
+
+    public SpiderWorld() {
+      Bounds = new Rectangle(0, 0, 1280, 720);
+      Player = new Spider(1280 / 2, 720 / 2, 200, 0);
+
+      Anchors = new ProfilingList<Anchor>(100, "anchors");
+      Anchors.Add(new Anchor(1280 / 2, 720 / 2));
+    }
+
+    ~SpiderWorld() {
+      Dispose();
+    }
+
+    public void Dispose() {
+      GC.SuppressFinalize(this);
+    }
+
+    public void Update(float modelTime, History<Input> input) {
+      Player.Update(modelTime, input);
+    }
+  }
+}