diff --git a/HipmunkPlayground.cabal b/HipmunkPlayground.cabal
--- a/HipmunkPlayground.cabal
+++ b/HipmunkPlayground.cabal
@@ -3,7 +3,7 @@
 Tested-With:   GHC
 Category:      Physics, Game
 Name:          HipmunkPlayground
-Version:       5.2.0
+Version:       5.2.0.1
 Stability:     provisional
 License:       OtherLicense
 License-File:  LICENSE
@@ -15,6 +15,10 @@
       This is a simple OpenGL program that allows you to see
       some of Hipmunk's functions in action.
       .
+      New in version 5.2.0.1:
+      .
+      * Show collision points.
+      .
       New in version 5.2.0:
       .
       * Updated to Hipmunk 5.2.0 (which uses StateVar).
@@ -32,12 +36,11 @@
 
 Executable HipmunkPlayground
   if flag(small_base)
-    Build-Depends: base >= 3 && < 5, containers >= 0.1 && < 0.4,
-                   Hipmunk >= 5.2 && < 5.3, GLFW >= 0.4 && < 0.5,
-                   OpenGL >= 2.4 && < 2.5, StateVar >= 1.0 && < 1.1
+    Build-Depends: base >= 3 && < 5, containers >= 0.1 && < 0.4
   else
-    Build-Depends: base >= 2 && < 3,
-                   Hipmunk >= 5.2 && < 5.3, GLFW >= 0.4 && < 0.5,
-                   OpenGL >= 2.4 && < 2.5, StateVar >= 1.0 && < 1.1
+    Build-Depends: base >= 2 && < 3
+  Build-Depends: Hipmunk >= 5.2 && < 5.3, transformers >= 0.2 && < 0.3,
+                 OpenGL >= 2.4 && < 2.5, StateVar >= 1.0 && < 1.1,
+                 GLFW >= 0.4 && < 0.5
   GHC-Options:   -Wall
   Main-is: Playground.hs
diff --git a/NEWS b/NEWS
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,13 @@
+Version 5.2.0.1
+===============
+ - Show collision points.
+
+Version 5.2.0
+=============
+ - Updated to Hipmunk 5.2.0 (which uses StateVar).
+ - Updated to OpenGL 2.4.0.1.
+ - Updated to GLFW 0.4.2.
+
 Version 5.1.0
 =============
  - Updated to Hipmunk 5.1.0.
diff --git a/Playground.hs b/Playground.hs
--- a/Playground.hs
+++ b/Playground.hs
@@ -2,6 +2,7 @@
 
 import qualified Data.Map as M
 import Control.Monad
+import Control.Monad.IO.Class
 import Data.IORef
 import Data.List (unzip4)
 import Data.StateVar
@@ -68,7 +69,8 @@
       stCarState :: CarState,
       stControls :: CarControls,
       stShapes   :: M.Map H.Shape (IO () {- Drawing -}
-                                  ,IO () {- Removal -})
+                                  ,IO () {- Removal -}),
+      stCollisionsVar :: IORef [H.Position]
     }
 data CarState = Stopped | GoingLeft | GoingRight deriving (Eq, Ord, Enum)
 type Object = (H.Shape, (IO (), IO ()))
@@ -78,15 +80,31 @@
 initialState :: IO State
 initialState = do
   -- The (empty) space
-  space  <- H.newSpace
+  space <- H.newSpace
   H.gravity space $= 0 +: -230
 
   -- Default objects
   seesaw  <- buildSeesaw space
   ground  <- buildGround space
   (car,c) <- buildCar space
-  return $ State space Stopped c $ M.fromList [seesaw, ground, car]
 
+  -- Add a callback to Hipmunk to draw collisions
+  collisionsVar <- newIORef []
+  let handler = do ps <- H.points
+                   liftIO $ modifyIORef collisionsVar (ps ++)
+  H.setDefaultCollisionHandler space $
+    H.Handler {H.beginHandler     = Nothing
+              ,H.preSolveHandler  = Nothing
+              ,H.postSolveHandler = Just handler
+              ,H.separateHandler  = Nothing}
+
+  -- Our state
+  return $ State {stSpace    = space
+                 ,stCarState = Stopped
+                 ,stControls = c
+                 ,stShapes   = M.fromList [seesaw, ground, car]
+                 ,stCollisionsVar = collisionsVar}
+
 -- | Builds the ground
 buildGround :: H.Space -> IO Object
 buildGround space = do
@@ -247,7 +265,7 @@
   ortho (-320) 320 (-240) 240 (-1) 1
   translate (Vector3 0.5 0.5 zero)
 
-  -- Add some callbacks
+  -- Add some callbacks to GLFW
   windowCloseCallback $= exitWith ExitSuccess
   mouseButtonCallback $= processMouseInput stateVar
 
@@ -323,12 +341,13 @@
 
 -- | Renders the current state.
 updateDisplay :: IORef State -> KeyButtonState -> IO ()
-updateDisplay stateVar slowKey  = do
+updateDisplay stateVar slowKey = do
   state <- get stateVar
   clear [ColorBuffer]
   drawInstructions
   when (slowKey == Press) drawSlowMotion
   forM_ (M.assocs $ stShapes state) (fst . snd) -- Draw each one
+  readIORef (stCollisionsVar state) >>= mapM_ (drawPoint CollisionPoint)
   swapBuffers
 
 drawInstructions :: IO ()
@@ -375,13 +394,13 @@
           y = radius * sin (r + angle) + py
       vertex' x y
     vertex' px py
-  drawPoint (px +: py)
+  drawPoint PositionPoint (px +: py)
 drawMyShape shape (H.LineSegment p1 p2 _) = do
   let v (H.Vector x y) = vertex' x y
   pos <- get $ H.position $ H.body shape
   color $ Color3 zero zero zero
   renderPrimitive Lines $ v (p1 + pos) >> v (p2 + pos)
-  drawPoint pos
+  drawPoint PositionPoint pos
 drawMyShape shape (H.Polygon verts) = do
   pos   <- get $ H.position $ H.body shape
   angle <- get $ H.angle    $ H.body shape
@@ -391,20 +410,25 @@
   renderPrimitive LineStrip $ do
     forM_ (verts' ++ [head verts']) $ \(H.Vector x y) -> do
       vertex' x y
-  drawPoint pos
+  drawPoint PositionPoint pos
 
 -- | Draws a red point.
-drawPoint :: H.Vector -> IO ()
-drawPoint (H.Vector px py) = do
-  color $ Color3 1 zero zero
+drawPoint :: PointType -> H.Vector -> IO ()
+drawPoint pt (H.Vector px py) = do
+  color $ case pt of
+            PositionPoint  -> Color3 zero zero 1
+            CollisionPoint -> Color3 1 zero zero
   renderPrimitive Points $ do
     vertex' px py
 
+data PointType = PositionPoint | CollisionPoint
+                 deriving (Eq, Ord, Show, Enum)
 
 
 
 
 
+
 ------------------------------------------------------------
 -- Input processing
 ------------------------------------------------------------
@@ -557,7 +581,14 @@
 advanceSimulTime stateVar steps = do
   removeOutOfSight stateVar
   state <- get stateVar
-  replicateM_ steps $ H.step (stSpace state) frameDelta
+
+  -- Do (steps-1) steps that clear the collisions variable.
+  let clearCollisions = writeIORef (stCollisionsVar state) []
+      step = H.step (stSpace state) frameDelta
+  replicateM_ (steps-1) $ step >> clearCollisions
+
+  -- Do a final step that will leave the collisions variable filled.
+  step
 
 -- | Removes all shapes that may be out of sight forever.
 removeOutOfSight :: IORef State -> IO ()