A topic near and dear to my heart. For my long commute I listen to old time radio shows via podcast and find it far superior to anything on the radio today. In particular, I am a fan of the Holmes shows with Rathbone and Bruce, sponsored by Petri Wine.
Anyway, the reason I am adding to this thread is to point out an alternative that I enjoy, which is a hosted podcast which broadcasts the episodes in order, once a week, with commentary. Waiting for the next one must be a lot like it was in the old days. This particular podcast has four other shows as well, one for each weekday. Check it out:
www.greatdetectives.net
or search for Adam Graham on ITunes.