I highly recommend listening to WFMT classical radio station (streaming, or in Chicago 98.7) while coding.
WFMT is the only station in the country that has announcer-read ads (i.e no jingles or pre-recorded commercials. Thus their commercials are non-intrusive.). Their announcers are excellent. The programming is accessible but a good mix. It's really great around Christmas.
Classical music for me helps me concentrate and, unlike my rock/rap doesn't distract me from intense concentration. (As a rule, I put on rock only when I'm doing work that doesn't require much concentration).
Don't like classical? It's actually good stuff if you develop a taste for it.
I just need enough to tide me over until I need more. -- Bill Hoest