I like listening to live365, there are lots of really great free internet radio stations on there to choose from.
Right now, I'm listening to the "Alt Class X" station out of Austin. It's all alt, new wave, punk, and post-punk from the 80s and 90s. I just heard in succession: Blondie, XTC, Thompson Twins, The Ramones, The Cars ("Candy-O," great track), Bowie, and now Oingo Boingo. Fun fun fun!