I was completely stunned at the beautiful music on this soundtrack. It is an absolute must for your CD collection.
Tori Amos' song, "Siren," is gorgeous, and it leads right into "Life in Mono" by Mono. This song has an incredibly unique sound due to the harpsichord, and the voice is nothing short of dreamlike. These are, I would say, my two favorite songs on this CD.
One of the greatest things about this soundtrack is that it is as eclectic as it is beautiful. Tori Amos, as was already mentioned, is present, but also is the fun, singalong "Uncle John's Band" by the Grateful Dead and Iggy Pop's "Success." There are also a couple of artists with songs on the CD that entice you to explore them more thoroughly because their contribution to this CD was so good.
I own about 250 CDs (last time I counted--many more now, I'm sure!) and this CD is in my top ten. It is hands down the best soundtrack I have ever heard.