"What is the book that changed your life? (not novels or religious texts)"
I think it's a wonderful way to connect in a less superficial way and learn a little more about each other. It's also a wonderful way to discover new books worth reading.
This is one of them (the full list is here):
Learn how to break the worry habit -- Now and forever! With Dale Carnegie's timeless advice in hand, more than six million people have learned how to eliminate debilitating fear and worry from their lives and to embrace a worry-free future. In this classic work, How to Stop Worrying and Start Living, Carnegie offers a set of practical formulas that you can put to work today. It is a book packed with lessons that will last a lifetime and make that lifetime happier! DISCOVER HOW TO: Eliminate fifty percent of business worries immediately Reduce financial worries Avoid fatigue -- and keep looking young Add one hour a day to your waking life Find yourself and be yourself -- remember there is no one else on earth like you! Fascinating to read and easy to apply, How to Stop Worrying and Start Living deals with fundamental emotions and life-changing ideas. There's no need to live with worry and anxiety that keep you from enjoying a full, active life!