This is a splendid little book by a MIT behavioral economist. The author did have a lot of fun doing his experiments in showing us how predictably irrational people are.

This book you can think of like Blink, Tipping Point, and Freakonmoics.
Some of the topics that stuck out were people's irrational infatuation with FREE, the differences in decision making for men in "aroused" and "cold" states (I want to see the grant request for that experiment!), people citing the Ten Commandments before a decision makes for a more honest decision, and finally the boundaries between social and market requests.

The way he described the experiments were a little convoluted. And I also wonder how people knowing they are part of an experiment behave differently.

Any person who doesn't understand why people can be so irrational should read this.