How can you have read Nietzsche and Camus and still think highly of Rand??? WTF!!!!
Rand's philosophy has its strengths and weaknesses, much like anything else.
Besides, the question was about which books in my life were the most powerful and meaningful, not which I happen to agree with the most. Atlas Shrugged, without a doubt, qualifies for this list; I read it as a freshman in high school, and (along with a number of my friends) was a hardcore objectivist for most of the next four years. Rand's ethics still hold some allure to me.