The Skeptic's Guide to the Universe – a fabulous weekly dose of science and skepticism done by a highly talented panel of amateurs. It's a lot like Skeptoid, except it's five to six times as long, covers far more topics (though not as in-depth), and has a lot more general science stuff. The latest science news, interviews with people in the trenches fighting for science and skepticism, Guess the Logical Fallacy, and a game show where they give you three science news items and you have to guess which is the fake (they they go over all three in detail). Great, great stuff. Easily my favorite podcast.