I started on Naked Economics by Charles Wheelan which is about how basic economic stuff shape our society and make the wheels go around. We had some basic economic theory in high school in the history classes, so I didn't hold my hopes too high but I've already learned some profound insights after having read the first chapter. It's a great book.
One of the first thing he writes about is the market and pricing system as a decentralised system for distributing goods. Think about it.
Having worked a couple of years on decentralised large-scale software systems for the internet, it makes a lot of sense. Centralised software systems have many scaling issues. They easily break down or are very inefficient, or both. But it's not exactly easy to construct a large-scale decentralised software system that is sustainable in the long run either. And software, as complex as it is, is nowhere near the complexity of a human society.
The book also points out flaws of capitalism and how government tries (or should try) to amend those, e.g. through taxes on goods that harm the environment and thus incurs hidden costs to all of us. I'm looking forward to some well-founded thoughts on globalisation.
So far the worst thing about the book has been the foreword by some other guy (I've never heard of him, but he's probably famous). The book would actually have been better off without it.