The 4-Hour Work Week
"Doing something unimportant well doesn't make it important."
The ultimate guide to break free from the 9-to-5 job you might have an to start your own business. In addition, the book shares a good set of principles about efficiency, effectiveness and how to work smarter, even if you stay in your day-to-day job.
1) The pareto law can be applied to pretty much anything. The 80/20 rule is something you should always think about, whether it is work related or not.
2) Quitting your day job and jumping into a new venture might not be the greatest idea. You can do a lot beforehand and without quitting your job, such as fleshing out the idea and testing it to see if it could work.
3) Whether you plan on starting your business or not, adopting a '4hr workweek mindset' will serve you well at work and in life.
READ IF: You need some inspiration and pragmatic tools for starting your own business.