I spend a couple of hours a day in my car commuting and traveling between locations. Podcasts are a great way turn "car time" into productive time. I listen to many, here are a few that I can't do without, give them a listen and I think you'll agree.
Pauldotcom Security Weekly.
Informative and Entertaining (always both, not always in that order). Sometimes not "work-safe" listening, but always worth listening to. A group of security pros offer up technical tips, how-to segments, discussions of current security news, the occasional interview and even "storytime" hacker stories.
"Two Former Federal Agents Talk About Computer Forensics, Network Security and Computer Crime." Another informative and entertaining podcast, mostly focused on computer forensics but covering a mix of topical and technical security news. Brett and Ovie also frequently feature interviews, again usually forensics focused, but not always. Always worth the listen, even if you don't handle incident response and forensics.
The Network Security Podcast.
The blogs and podcasts from Martin McKeay- Martin is a prolific blogger, podcaster and video podcaster. Although he has an information security focus, with PCI a frequent topic, Martin also ventures into other areas- I especially enjoy his coverage of electronic voting systems and his exploits in the guise of his alter-ego, Captain Privacy. Martin's "creative output" has recently been re-invigorated, and I'm glad about that.
"Steve Gibson, the man who coined the term spyware and created the first anti-spyware program, creator of Spinrite and ShieldsUP, discusses the hot topics in security today with Leo Laporte."
Security Now has some great great information, especially some of the earlier shows on encryption and the foundations of TCP/IP. This show targets the "power user", not the security pro- keep that in mind as you listen, otherwise you may find yourself screaming at your MP3 player occasionally.