There were recently several interesting music related podcasts from San Diego's KPBS These Days:
- The Bird and The Bee
- West Indian Girl
- Oxford American's Southern Music Issue
- Earl Thomas Performs In Studio (Video)
- In Studio Presentation Of A Stradivarius Violin
When I'm in the mood for the blues I always turn to The Roadhouse podcast.
The Magnatune "great pianist" podcast is very good if you want something 'lite' playing in the background.
The Alternative Classix Podcast is a well produced and researched 80s 'new wave' radio show you will not be disappointed with.
- SomaFM's Grove Salad
- DJ Amber's iamthedj podcast
- DJ Steve Boy's podrunner
- Radio 538: Tiesto's Club Life
If you want something more mellow but still pretty electronic then check out the Ultima Thule Ambient Music podcast.