I've started doing a lot of non-fiction reading as of late. It's really rewarding - nice to branch out from your academic specialty and see what else the world has to offer. You would also be quite suprised how much you can read if you just read for an hour or two before going to bed at night. I've read all of the following (except the last 2) in the last 8 months or so.

Thinking fast and slow Teaches you about cognitive bias, and various other phychological issues. I found this extremely eye opening.

The evolution of cooperation - how cooperation can evolve between self interested agents. A fascinating read.

A random walk down wallstreet Learn how to manage your finances. And, understand what the stock market is. This might be my favorite book here. If anyone says they are "making a killing on the stock market", or something along those lines. They are either lying, or clueless. But, putting your money into the stock and bond market is a FAR better strategy than a savings account in the long run.

How not to be wrong Great book about common mathematical fallacies.

Plato's Republic A classic philosophical work.

How to solve it. Classic book on problem solving.

A guided tour of complexity. Layman introduction to complexity theory, quite interesting and lots of insight into biology, finite automata, math... The world is truely an incredibly complex place, but we tend to forget this especially in engineering when we work with nice simple "spherical cow" type problems a lot of the time.

New ideas from dead economists. I'm reading this right now. Good book if your interested in some of the history of economics. Also gives an introduction to modern economic debates.

The mathematical experience. I haven't started this one yet, but I've heard it's good.

Flatland. I read this in highschool, but it's one of my favorites. It is technically fiction, but a nice book on thinking about higher dimensional space. This book was (so I hear) very famous in the 80s, but less well known now.