This might be sacrilegious to say but I am going to say it anyway.
I like the The Dave Ramsey podcast. It is 40 minutes a day, 5 days a week and is interesting. As well, it is a good reminder to keep my finances in order.
When I am driving at night I like listening to DNTO from CBC Canada. Definitely Not The Opera, picks a particular topic for the week, then combines a bunch of short interviews and interesting stories on the topic. It is a collection of stories from great story tellers.