Has there been a book that has changed your life? Maybe just a little bit?
Please Understand Me by David Keirsey and Marilyn Bates. I read this when I was an undergrad. It was the first time I ever heard someone express that it wasn't bad to be shy or introverted. And coming from a family of extroverts, this was a big deal.
I also learned in this book that my personality type was an INFJ. As a rare type, it made more sense why often others didn't get me.
Needless to say it was a very eye-opening book. It helped me understand myself as well as other's reactions to me.