Pandora and the Music Genome Project

First and foremost, if you love music, if you love free music, if you love finding new music, go to Pandora. It's part of the Music Genome Project and it allows you to create your own "radio stations" where you have relative control over what is played.
How does it work? (You can go to the MGP link above and get the technical version or you can read my generalized version.)
You type in an artist or a song, and Pandora picks out the elements of that artist or song and finds more music with similar qualities. That music is added to your station, but it doesn't stop there. You can give each song a "thumbs up" (play more music like this!) or a "thumbs down" (never play this song again!). There's even an option to take a song off the station for a month if you get tired of it.
Pandora has exposed me to many new artists, and it's always the first place I go if I'm going to be online for a while. The potential for this site is to boost the exposure of artists who would otherwise "go under the radar" so to speak.
On a side note, the RIAA is demanding major royalty fees from Pandora, to the point where it makes keeping Pandora afloat, quite difficult.

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How can teachers use Pandora in the classroom?
I think that Pandora gives students the oportunity to learn about analizing music. They can create a station, or go a a precreated station by the teacher, listen to a few songs, and then explain what elments the songs have in common, and how they differ. Pandora also provides some of that information if you select the "Why is this song playing" option, so it can even teach the students what to listen for!