I've always had a bit of a soft spot for the Book of Revelation, as essentially being a form of early science fiction, not to mention having avidly read all the Just William stories at just the right age*, so no wonder that Messrs Pratchett and Gaiman made such a brilliant book around those themes. Superb!
*Now i suddenly realise where my love of getting wet and muddy on a mountain bike must have come from.