Here's a list of some great books that have changed the way I think and operate:
The Alchemist - The first book I recommend to everyone. It's the story of life.
The Four Agreements - Don't take anything personally. This book helped me stop that.
The Shortness of Life - The truest words about how we waste time.
Who Moved My Cheese - Change is inevitable.
How to Win Friends and Influence People - I thought I knew how to win friends, after the 6th person recommended this one, I figured out I was wrong.
Zen Mind Beginner's Mind - How to remove the assumptions and see everything new for the first time.
It's Not How Good You Are, It's How Good You Want to Be - It's all about how you handle what situations life gives you.
2 Second Lean - The easiest approach to learning about continuous improvement and fixing what bugs you. Lean is invention and innovation.
The Goal - After working in factories for a while, the lessons in this book made so much sense.