Basic questions about preferences and the usual economic assumptions:
Choosing the Right Pond by Robert Frank. Maybe it's not how much stuff you have, but whether you have more stuff than the other guy. For a more economic approach to questions of human nature, and in particular questions of status, Choosing the Right Pond is an excellent book. Frank attempts to resolve some "puzzles" that appear when economic theory is applied to real life.
The Red Queen by Matt Ridley. The Red Queen explores the evolutionary history of sex and its effects on human nature. Through numerous examples from nature and human society, Ridley traces biologists and psychologists views on the significance and "goals" of things such as monogamy, gender and race bias, puberty, feminism and beauty. It serves as an excellent introduction to the realm of evolutionary psychology. For the non-scientist, it also serves as an introduction to evolutionary psychology.
The Moral Animal , by Robert Wright The influence of human evolution on everyday life. Wright, a journalist (former editor of the Economist), has researched current trends and conclusions in the field, and has packaged them in an excellent book that explores the everyday phenomenon of marriage, childrearing and the like.
Passions within reason: the strategic role of the emotions, by Robert Frank. Why getting angry and falling in love are rational, in different circumstances. So, if even our emotions are rational, why not analyze them using economic tools?
Economic Choice Theory : An Experimental Analysis of Animal Behavior by John H. Kagel, Raymond C. Battalio, Leonard Green A fascinating look at how useful economic ideas are for describing animal behavior.
Politics, Policy, History:
Stone Age Economics, by Marshall Sahlins. I haven't read this in years, but I remember it as an attempt to use economics to analyze behavior in primitive societies. Maybe there are more recent attempts to do the same, if so I'd appreciate hearing about them.
The rise and decline of nations, by Mancur Olson.An intriguing explanation for the decline of civilizations from Rome to the U.S. (well, it was written when Carter was President) based on economic theories about how special interest groups affect political decision-making.
Peddling Prosperity, by Paul Krugman. Examples of the interaction between economy theory and real world problems.
Manias, Panics and Crashes : A History of Financial Crises, By Charles P. Kindleberger. "An informative and entertaining history of financial crises from the timeof the South Sea Bubble in the early eighteenth century to the worlddepression of the thirties and the mini-panics of the early seventies."(N.Y.: Basic Books, 1978).
Against the tide: an intellectual history of free trade, Douglas Irwin. Some arguments for and against free-trade over history, from Aristotle to Adam Smith to Krugman.
Game Theory Evolving, by Herbert Gintis. An excellent intro to what game theory is, with an evolutionary slant that makes for interesting reading. Starts with simple games, assumes you know some economics but no game theory.
Thinking Strategically, by Dixit and Nalebuff. What game theory is and how it can help you succeed in business and life.