Was Leonardo Da Vinci a…cryptographer? That’s one of the premises behind Dan Brown’s The Da Vinci Code, which has been getting a lot of media attention. Wiredhas a more informed take than most on the cryptography that forms the background to Brown’s intricate mystery, while The New York Times can’t stop reminding the world that the book made the number one slot on the bestseller list of, guess who, The New York Times. Speaking of the marketing angle, Random House and Dan Brown have a challenge for all you sleuths out there.