The 4-Hour Workweek by Timothy Ferriss claims that you can earn more by working 4 hours per week than you currently make working 40 hours. I don't know about that, but the book does contain some good advice to use your time more efficiently.

A good chunk of this book focuses on starting and running your own business. Ferriss covers delegation of authority, marketing strategies, distribution options, and setting prices.  I am not really interest in starting a business, but I still got some useful information from the book.

I most liked his discussions on time management and how to free up your schedule by being deliberate about how you spend your time. 

Her is some of Mr. Ferriss's professional advice:
-Check email less frequently and at set times during the day. Never first thing in the morning.
-Avoid meetings. Ask for the notes instead.
-Eliminate those tasks that are unimportant and/or unproductive
-Delegate tasks you cannot eliminate. You can outsource many of these tasks for a small fee.
-Reduce interruptions. Require a clear agenda before meeting with someone
-Let everyone know you are very busy (even if you are not)
-Use autoreplies and FAQs to respond to questions

He also includes some advice about life beyond business
-Don't defer your rewards until you retire. Instead, take "mini-retirements" several times a year to enjoy life.
-When your work week reduces to 4 hours, fill your time with something fulfilling
-Define your goals. Do you want to be a millionaire, or do you want to live a millionaire lifestyle?

This book has its flaws. It is padded with testimonials (labeled as case studies) and Ferriss comes across as arrogant.

Some of the material here is out of date. Is Yahoo really the best place to launch an online store? Many of now the communication services he recommends are now available free from cell phone providers. Some of the companies and services he recommends no longer exist. But he maintains an active blog to address these changes.

I don't buy into the goal of the title. I don't aspire to work only 4 hours per day, so I don't set that as a realistic goal. But I did find enough useful information in this book to make it worthwhile.

The single biggest impact the book had on me came about halfway through reading it: I set it down and scheduled a vacation for next week!