I'm a Postman so I get 4 to 5 hours every day with my headphones on and I'm really chewing through some stuff. I'm after science (evolutionary biology and anthropology especially), history of religion and comedy. Old sci-fi audio books are also a favourite.
I'll give JW related stuff a shot if it's short and factual but it's not at the top of my list.
Let me know what you're enjoying. Cheers.