Wow, it's actually more difficult than I thought to pin down a specific book, as I think every book you read will have an impact in some way. For me I am tempted to choose Harry Potter and the Philosophers Stone, I read it when the movies came out and there was something about being the same age as the protagonist that I know for myself and for others in my generation helped us to connect with it, and more importantly, each other. While not life changing, it certainly helped that just when starting at secondary school and experiencing all these changes and uncertainties, the books and movie came along and gave us all a sense of being connected and having a place in the world; and it's a thing we're always going to have with us, maybe our generation should be called the Potter generation as I know in 20, 40, 60 years that if someone mentions a Harry or a Ron or a Hermione that we'll all be able to sit around and talk about the impact the books and movies had on us. Whoa. Harry Potter is our Vietnam.