Not exactly podcasts, but if you have ITunes, you can get iTunesU. There are a couple of great lectures on there I would recommend:
The first is about Hannibal (Punic Wars) through Stanford by Patrick Hunt. Very similar outline to what Dan Carlin did. Pet peeve: he pronounces cavalry as "Calvary" OMG it drove me crazy. Otherwise a great podcast and more in-depth than Carlin's.
The second is a series of lectures through UC Berkeley, specifically Western Civ. from 1453-present. Some of you may be rolling your eyes at this one, but the lectures are great. The specific one I mention is the Spring 2008 series of "History 5" class. I actually downloaded all these and listen to them on occasion. The prof. is very even handed & I would recommend it as a nice general overview of some of the major events of the last 500 or so years.
One podcast not mentioned yet is the "The Napoleon Bonaparte Podcast". It has around 19-20 episodes roughly an hour long.... done by a huge Napoleon fan and the author of "Napoleon for Dummies". If you slog through this beast of a podcast, you'll have a new appreciation for the Corsican genius. Don't let the "Napoleon for Dummies" part make you think this a juvenile effort.... it is in depth and top-notch.