Linerider

Part Jackass stunt, part physics lesson, Line Rider encourages users to "draw" their own ramps, hills, and slopes with a pencil tool, then sends a virtual sledder (wearing a red scarf) along the route until he swoops, swerves and crashes. Build an elaborate enough course and you'll feel like a little kid playing in the snow again, zooming downhill, popping up in the air, wiping out on a ramp jump a la Evel Knievel. Check out http://www.deviantart.com/deviation/40255643/