If you've got some time to kill online, or you'd like to join an interesting conversation about the impact of books, follow the "books that changed my life" thread on Twitter. (I'd say, at this moment, people are responding via Twitter at a a rate of about 5 tweets a minute.)
All you have to do is click here and read the tweets, all marked with the #booksthatchangedmylife hashtag. (And, if you have a twitter page, tweet your own response!)
Publishers, book bloggers and readers everywhere are getting into it, and answers range from classic novels to reference texts to picture books.
If you're not into tweeting, feel free to leave your answer in the comments right here on The Book Case.
Update: #booksthatchangedmyworld is also a popular topic on Twitter.