Toy project for Google's HTML5 Hackaton (Aug 11th, 2011, Mountain View: http://www.eventbrite.com/event/1910202467)
Completed in 2 hours of collaboration. Later we found a better JS library for the purpose – http://code.google.com/p/box2dweb/
Live demo: http://dybskiy.com/bike
Use left/right arrow to accelerate/brake, and up/down to tilt the bike.