Podcasts are wonderful, a change of pace in my day. I listen to them while I work and like to think that I'm making the most of my time by working and educating myself at the same time. There's not much to say about them really. There is a podcast out there for many, many different subjects. Here are the ones that I catch every episode of:
http://www.geekson.com/-I've mentioned my love for Geekson before. Very entertaining and intellectual conversations with a great format and a surprising variety.
http://www.basicbrewing.com/-James Spencer provides a wealth of knowledge for both the beginning home brewer and advanced. He arranges some pretty impressive, informative interviews with some big names in the craft-brew arena including the Godfather, Charlie Papazian.
http://www.radiolab.com/-This is probably the one I quote the most. It is a very well produced show that offers very interesting studies in science and life. I use information gathered on this podcast in many a discussion.
http://www.dancarlin.com/-Dan has two podcast, Common Sense, which is a political show if you like the right side way of thinking, and Hardcore History, the one I listen to. Dan is very well prepared for his shows and knows a lot about a lot of things history. He makes you want to know more all the time, I like that.
http://www.craftbeerradio.com/-This show is a novelty. Two guys sit around and drink beer and tell you how good/bad it is. I am an occasional listener because they give good "beer history" lessons sometimes and that is kind of neat to hear how things develop.
There are a few others that I might stumble upon from time to time, but these are the ones that I listen to so much that I feel like I "know" the hosts. If anyone has any more suggestions, I'm always up to try a new show, and if you haven't checked these out and them seem interesting, give them a try.