A cow orker showed me this one. The game is called Porrasturvat, a word the author vaguely translates to English as ‘Stair Dismount’. It's a physics simulation, the physics in question being just how much damage you can do to somebody when you push them down a flight of stairs. It's more than a little scary how much enjoyment one can get out of the simplest cruelties.

(This was on slashdot a few days ago, but I missed it)