Physics don't get much better than that...
...in flash. Although knowing you, you'll find a way to prove me wrong :P.
Anyway, the concept was brilliant, a nice original touch to the platform genre.
The gameplay was the center of the game, and was also very good, although you could have a more gripping 1st level to make the gamer want even more.
The sound was very good, and fitted in with the gameplay well, along with all the Panning effects and the rock sounds ;).
All in all, a very unique, vibrant and fun addition to the platformer era. I hope it gets the rightful score it deserves :).
10/10.
PS. Check out the 'Reg' lounge, there's a few comments there :).