I'm in love. With a woman. Her name is http://www.pandora.com/.
I think you'll fall in love with her, too.
Pandora is the culmination of project started in 2000 which assembles hundreds of musical attributes or "genes" into a very large Music Genome. To quote the Pandora site:
Taken together these genes capture the unique and magical musical identity of a song - everything from melody, harmony and rhythm, to instrumentation, orchestration, arrangement, lyrics, and of course the rich world of singing and vocal harmony. It's not about what a band looks like, or what genre they supposedly belong to, or about who buys their records - it's about what each individual song sounds like.
So what does this mean for you? Pandora allows you to create, for free, "stations" by defining musical elements you like, specific singers, bands, etc. There are no audio commercials, just free streaming music chosen specifically for the qualities you indicate. Furthermore, you can give individual songs a thumbs up or down to further guide Pandora to the types of music you like. Also, unlike radio, if you don't like a song you can just push a button and move onto the next.
Check it out! But beware, like a new relationship, you might find yourself wanting to spend all your free time with her!!