One of the secrets of doing physics is to keep in mind what you don't know. The trick is to get from what you know, to what you want to know, without going through what you don't know.
-Thinking Physics (page 300)
I don't know why I never bought this book before - I've looked at it a dozen times over the years. This time I had a 30% coupon at Borders, saw it again in the science section, and here it is.
Thinking Physics by Lewis Carrol Epstein is a wonderful book, full of (seemingly) simple and occasionally complex physics problem, most inspired by everyday objects and situations. You're supposed to think about the problem and try to solve it before looking at the answer. In many cases, the "obvious" answer is wrong, and Epstein's explanations show you why, and also show you how the right answer is really intuitive if you think about it the right way. There is very little math here - problems are solved by physical reasoning, analogy, symmetry, and various heuristics, supported by simple sketches.
This is the Bathroom Reader for science nerds, but you don't have to be a science nerd to enjoy and learn from it. I'm an optical engineer, but I find that I'm learning or re-learning things about light that I thought I understood (or perhaps understood in an equation sense). This book helps you to see even familiar things like shadows and mirrors in new and fascinating ways.