Eli Bendersky's website As its secondary title suggests, this book is about "How to get more done without driving yourself crazy". It collects productivity and time management tips from many experts in the field, including the authors themselves. All the main topics are covered: Focus, Planning, Organization, Taking Action and Learning - these are further subdivided into sub-topics.
This is a very condensed book that successfully resists the temptation for obesity that many books in the genre fall for. At 130 pages, it is slim and packed with useful information.
Naturally, such brevity comes at a price - the book at many places isn't as comprehensive as one would like and only stays on the surface of things. But for some applications - this is exactly what's needed. Especially as a reference, I think this book is very good because once you've learned the techniques, you only need a short, focused reminder of the most important points.