In this physics game, all you have to do is set a comet flying into space in such a way that it doesn't crash into one of the peaceful blue planets in the vicinity, killing off the peaceful, grass-loving sentient creatures that write poetry and raise their polite, clean children there. Okay, I'm reading a lot into a bunch of circles, but I like to feel involved.
Orbit [2DGames] (via Metafilter)
