WOOT! I was listening to Beethovens' Serenade for flute, clarinet and guitar, Op. 8 on b.com and was playing with skins in WMP. It landed me on a fairly uninteresing visualization, but I have to say that the fire storm or ocean waves visualization (under bars and waves) is really mesmorizing. You can see the individual notes of the flute and clarinet dance around. Very cool.
So, when you have some time to dither, try some visualizations, on a song with only a handful of instruments. There are some ho hum ones, but some will knock your socks off, I think.
If only I could fly on my own wings.