I have been an avid reader since a young age and around the time I turned 15 I discovered and quickly became scornful of self help books.

However, one self help book which I recently discovered and completely changed my life is "Rewire your brain" (ISBN: 0470487291) which offers explanations of many things from a neuroscience perspective and includes some practical anecdotes etc.

I would recommend it to essentially anyone, and all I could think while reading it was "why is this book not mandatory reading for all humans?".

FWIW.