ok, i was at school the other day, and saw this kid playing some game on his computer, but with itunes up, and it had some crazy background, and when i asked him, he told me it was the itunes vizualizer.

most versions of itunes have the vizualizer, so to acess it, go to view, then go to the bottom and select show vizualizer. then press the play button and watch as your computer responds to the music in such crazy ways, you'll think your on drugs. Jk