A couple of interesting and informative podcasts that I've run across:
The Pilot Cast: A podcast for pilots, by pilots (their tagline). Discuss everything from airplanes to zulu time with guests in the relevant fields. Shows run between an hour and hour and a half.
http://pilotcast.libsyn.com/The Finer Points: A podcast by a flight instructor discussing various aviation topics to promote safety and understanding.
Shows under 10 inutes in length each.
http://www.thefinerpoints.net/
