It's a cool idea but it gets boring quite fast. Maybe you could add some other things that interact with the objects in different ways.

Definitely neat, and what was there was presented nice. The sound and particles for particles colliding is really tactile and cool! I like sandbox-y type games, but I do wish this had more to play with. There's no goal, which is fine, but if you don't give the player a goal, you should be sure to give them enough tools for them to forge their own goals. The physics themselves feel nice, and could definitely be a fun start to a simulation game, but it needs a little bit more bulk to keep me once I've been drawn in.

I enjoyed this. It was fun to watch as the particles did their thing. Nothing more to say really.