A podcast is basically an on-line, on-demand radio show.

The Primal Edge Health Show is a relative newcomer, the host is very gung-ho on ketogenic diets, mostly as it relates to fitness. I also like some of the Smash the fat interviews, but people with delicate ears might want to turn down the volume a little bit.

I find Jonathan Bailor gives a pretty good interview. Often a guest that I've seen in two or three interviews will get repetitive--the questions so obvious, that it's essentially like watching the same interview again and again, some interviewers are better at covering new ground than others.