Have you guys played this game? It is completely awesome.
If you get it for Xbox360, you can turn on your other Xbox controllers and use them as trance vibrators. That is, you can put an extra controller behind your head and under your feet and anywhere else and the controllers will vibrate to the music while you play the game. Beyond that, the game is insane.
It's available for PS2, if you have that console... but if you have a 360, it's only 10 bucks and totally worth it.