For an excellent eclectic musical podcast, check out RANDOMwerks. You might hear Prince, David Bowie, and the Smiths, and then Billie Holliday or someone you’ve never heard of, but will enjoy.
The best part is that you can subscribe via iTunes and just stream it from your computer as you work–no need to change CDs or worry about illegal mp3s being found on your machine.
Strike a blow against pabulum corporate radio AND boredom… at the same time! Brilliant!