This was the book that made me realise the "depth" of Dan Brown novels: that the allusions and references to history/art/science/religion are just that, allusions and references. That the author doesn't actually have a clue what they're talking about.

I'd had the benefit of being ignorant of majority of the subject matter for Angels & Demons, The Da Vinci Code and The Last Key, but as a teenager I knew enough about computing and cybersecurity to realise that all the technobabble was just nonsense. Special points for "Rotating Cleartext", whatever that's supposed to mean.