If you like my blog, you should also be aware of at least one other blog that is around: The Do It Yourself Scholar, or DIY Scholar. DIY Scholar is run by Dara, who manages to keep track of whatever free material is available from the world's universities and informs us how to obtain that stuff.
Since a lot of these are recorded lectures and among those are quite a few podcasts, Dara and I frequently report about the same material, but if you are interested in academic level educational material, a lot more can be found at her site. She will be the first to let you know what new institutions have started sharing their audio on iTunes U. She also helps using that directory and gives technical tips for converting files (where needed). Her attention goes not only to audio, but also to whatever course material is available as text or video.
There are numerous podcasts I have discovered thanks to Dara. Recently, thanks to her, I found out about the Teaching Company, which delivers a huge amount of streams, but also a new podcast. I might be reviewing the two lectures about the historical backgrounds (or lack thereof) for Dan Brown's best-seller The Da Vinci Code. On Dara's site you can already read a review about the lecture addressing the extinction of the dinosaurs.