The best by far that I listen to is Bloomberg on the Economy. Tome Keene is an outstanding host and gets great guests. Its more on an economics podcast than a trading podcast.
I enjoy Frank Curzio's podcast though its pretty unsophistocated. Definitely entertaining. I also like The Disciplined Investor.
I think you gotta take all the stock market podcasts with a very big grain of salt but they can be informative.
Mad Money Machine,
NPR planet money podcast,
Econtalk,
Demandside (but only the stuff featuring recordings on established economists ie Krugman and Stiglitz, ALan Harvey's readings are offputting).