Not just for reading, but for reference purposes as well.
The chapter in Applied Economics on Free and Unfree Labor has more facts about slavery that run counter to the conventional wisdom than I've ever read in one place.
I have to call the man a genius because there's not a more superlative word.
He is a true Renaissance man in times when Renaissance men are practically nonexistent.
Black Rednecks and White Liberals was the first book I read by him. The man is flat-out amazing.