Timothy Ferriss basically turned his body into a laboratory. Having read all sorts of (sometimes conflicting) advice about a range of topics, including losing fat, adding muscle, healing from injuries, and improving sleep, he decided to test them out on himself and a bunch of others. Using the latest technology in advanced gadgetry, he figured out how to dramatically improve his life in many efficient and feasible ways. He gives us his results in The 4-Hour Body.
This is probably the best book I never finished. It is highly informative, but on so many topics that it is best used as a reference. The topics in which the reader isn't interested can be ignored, but the book is extremely helpful with respect to the topics in which the reader *is* interested.
An interesting quirk for value investors: Ferris is clearly a huge fan of Charlie Munger, and quotes him repeatedly. Ferriss discusses a few mental models that are helpful in understanding a few of the tricks he offers readers.
One thing that concerns me a little is that while a lot of the tricks Ferriss discusses and uses himself may indeed work at solving a problem, the long-term effects in some cases are relatively unknown. Proceed with caution! Most of the advice is perfectly harmless though, in my opinion, and readers would be well-served to take much of it in order to live healthier.
Ferris impressed me with his strong bias for evidence and his willingness to create evidence (with himself as the guinea pig) where he was unsatisfied with what's already out there. As a result, I've been inspired to read Ferriss' most popular book, The 4-Hour Workweek.