There are a good number of interesting podcasts out there.
For those who dislike the medical con, I’d recommend the QuackCast, which surveys the medical literature on quack medical treatments, and it comes free with a delicious dry sense of humour. I particularly enjoyed Quackcast 26, which admittedly was just a piss–take.
For those who dislike common ignorance, try the Skeptics’ Guide to the Universe. This is more entertainment than survey, but all the same there are often good, well–informed & entertaining discussions.
I’d be interested to find more good science & engineering podcasts, ideally surveys with a sense of humour a la Quackcast. For example, Microsoft produce some very interesting computing science podcasts, but unsurprisingly these are orientated towards their products.