Simple, and somewhat braindead, particle system for Flash.
It'll comfortably get about 5k particles at 60Hz on a 2GHz MacBook Pro debug player, or about 10k - 15k on Windows. Frankly, that sucks, but it is Flash after all. Performance takes a nose dive on aforementioned MacBook Pro after 10k particles.
Press ALT to get bigger particles. You size queen you.