I ran into Erwin Coumans at the Open Source Pavilion at Siggraph where he showed me the 15 entries that he has received for his Bullet Physics Contest. Erwin is the original developer of the Blender 2.0 game engine and he is now working for Sony where he is developing the Bullet Physics Library for the PlayStation 3. Sony has allowed him to open source part of that library and he has been busy implementing it in Blender.
The Bullet Physics Contest is now closed and Erwin has compiled screengrabs into the video which you can see below. You can also download demos for each of them from the Bullet Website. After you have tried them all, don't forget to vote!
I am impressed both by the results of the contest and by the amount of energy that Erwin is putting into developing and promoting Blender's interactive capabilities. Thanks, Erwin!