Everyone must already own The Da Vinci Code. Angles and Demons, the prequel to Dan Brown's mega best seller, reigns supreme at airport bookstores. It's not hard to see why: the plot, which focuses on an improbable attempt by the ancient order of the Illuminati to destroy the Vatican (using antimatter, natch), makes perfect sense after being lulled into a state of travel-induced half-sleep. It's also the type of book that has made Brown lots and lots of money.