What books have changed your life?

Question:

What books have changed your life?

Tell me the title and author of a book that changed your life.
In what sense has it changed your life or view of the world? What makes this book so special?
Would you recommend it to others?
What genre is it?
Have you read other books from the author? Did they have a deep impact on you as well?
Your answer can include more than one book. I will be happy to read all answers (and maybe some of the books...) :))

Best Answer - Chosen by Asker: Johnny Got His Gun by Dalton Trumbo. Its an antiwar novel and it is fantastic.

It inspired me to write my novel, which I wont reveal the name of or when it is coming out because this isn't the place for that.

The Picture of Dorian Gray by Oscar Wilde. It is the only novel Wilde ever wrote. It is very philosophical. Reading that book took me from being a high school drop out at the time to an eventual college graduate and now a high school English teacher.