I had the chance to chat with a fellow music professor friend today and he clued me in to Grooveshark. Maybe you already know about it for streaming music. It is much like Pandora, but unlike Pandora, I can create playlists and email them to students for study purposes.
One of the many challenges to online or face to face music teaching is getting the music accessible to the student without breaking any copyright laws. The History of Rock course is especially challenging since so much of the music is too unreasonably expensive for text book publishers to buy the rights. Grooveshark takes care of the copyright issues since no music is downloaded, and the students, either online or face to face, do not have to purchase every track to for study purposes.