Andy Kessler has a pdf version of his book How We Got Here available for free from his website. The book is about technology’s contributions to history and increases in the standard of living. Kessler was originally trained as an engineer, and he takes an engineer’s approach to the situation.

I read Kessler’s book Running Money a couple of years ago and his writing style is engaging and accessible. He also wrote the first chapter (titled Signposts in the Fog) of Just One Thing. He also has a pretty good blog here.

(The pdf is 212 pages, ~670kb.)