Any good freeware music games?

[One Man Freak Show]

I've tried Frets on Fire and Stepmania and don't really care for them. FoF lags horribly and StepMania's songs are only good if you get them from a site which makes good sync things. Also, I looked at Audiosurf or whatever it's called and I don't understand it, and I don't know how to play without the beta version or whatever.