Great book, couldn't put it down. Remember that it IS fiction. Dan Brown does an outstanding job building his fiction on fact, and also making his fiction sound like facts.
Interestingly, almost everything that he talks about regarding Opus Dei IS factual. Sorry, a band of spikes digging into my leg as penance doesn't make me want to run out and join them.
Frolf suggested reading his other books a while back. I read Angels and Demons and Digital Fortress. I thought A & D was every bit as good as Code, similar themes and storyline. Digital Fortress was good but not as good as the others.