I read The Fountainhead when I was 18 and I found it absolutely mind blowing. Needless to say, I was quite impressionable at the time, and a young atheist. The book served as positive reinforcement to me, emphasizing on belief in oneself, rather than belief in God. It was also the perfect fodder for my teen angst, wrapped in delicious ideological and intellectual mysticism. This led me to be an unapologetic jerk to everyone around me for a year or so. I laugh thinking about it now.