I'm loving www.pandora.com, a free, personal, online radio service.  It's a great way to find excellent new music and hear your old favs, too.  Wow, is there ever a lot of good music out there! 

One neat feature of the site is that, in addition to letting you give a thumbs up or down for songs, pandora will say why it picked a particular song for you.  E.g.,

"Based on what you've told us so far, we're playing this track because it features acoustic rock intrumentation, a subtle use of vocal harmony, mixed acoustic and electiric instrumention, acoustic rhythm guitars and many other similarities identified in the music genome project."

Another muscical characteristic I've found that I like is "extensive vamping".

My personal station and some neat songs I've bookmarked are at

http://www.pandora.com/people/bob0595