Economic markets, that is. John McMillan's book Reinventing the Bazaar covers a lot of the modern economic theory (albeit in a practical manner) about markets. I like his statement that "liberals" oppose the free market and some of the best ideas about how to help poor people, and "conservatives" love the free market so much that they love ideas that would destroy proper market functioning. McMillan keeps coming back to the idea that markets depend on proper government regulation in order to function best: his best example of this is the comparison between Russian shock therapy in the 1990's and China's unprecedented growth during the same time period.
I enjoyed his description of the Tsukiji fish auction in Japan, where $25M of fresh fish is auctioned every morning. My friend Mike Epstein has said that it is quite a sight!