I'm a big fan of the podcasts at zencast.org. Particularly those by Gil Fronsdal. He is a Vipassana teacher and gives talks in a very humble, down to earth manner.
I'll agree with this. Gil has an incredible manner of speaking. Some of the other zencast podcasts have people that tend to lecture at you on their topic, whereas Gil just seems to draw you in to the way he leads his life, warts and all. I actually miss my one-hour commute (now a 5-minute bike ride) that gave me time to listen to him.
