For Cambridge residents: Check out the basement of the Harvard Bookstore on Mass Ave. There are LOTS of very cheap books. Here are some of the books I found:
The Universe and the Teacup by K. C. Cole
The Greatest Show on Earth by Richard Dawkins
Fabric of the Cosmos by Brian Greene
Euclid in the Rainforest by Joseph Mazur
The Stuff of Thought by Steven Pinker
The books by Cole and Mazur are about how mathematics explains the world. Dawkins' book is about the evidence that supports the validity of evolution. Greene's book is about the nature of space and time (aka spacetime as Einstein called it). Pinker's book is about how language provides a window into the workings of the human mind.
