Dan Carlin's Hardcore History

Addictive for the lengthy commute. So far I've listened to:

Countdown to Armageddon (5 parts, WWI)

Radical Thoughts (on the evolution of the idea of a "Red Menace" in America)

Thor's Angels (4-hourson European tribes after the fall of the Roman empire in 472 and in the ensuing 1000 years, what used to be known as "The Dark Ages")

Logical Insanity (a history of aerial bombing between 1895 and Hiroshima)

Wrath of the Khans I & II (long series on Genghis Khan)