I love Pandora the internet radio site. I have been a user of this site for a while and have a station that I have tuned to my tastes. Mostly women's vocals with a rock/folksy sound. Recently I added some hard rock to the station and now I get a lot of punk suggestions which is excellent since my station was a little too consistently soft for me. Now I have a more eclectic selection and it is filled with music I otherwise would never have found.
Pandora is nearly the perfect service for someone like myself who enjoys listening to music but spends no time learning about bands, or particular sounds. There is no way I would have found out about bands like "Yeah, Yeah, Yeahs" or "Giant Drag" without Pandora.