You guys should really read the Dresden Files, I'm not being fair in my explanation of the "system", Butcher really built a mythology that's awe-inspiring in its clever simplicity. The fucker takes pretty much every single lore and mythology into the "real world", and makes it work seamlessly. That Bram Stoker wrote "Dracula" exposed to the world at large the weakness of the Black Court vampires (sunlight, stakes, etc) made them almost extinct, Merlin was a real historical figure, Odin and Michael the Archangel are competing for attention of our hero and all while the Leaninsidhe from Celtic mythology plays with him while running from Queen Mab of Shakespeare fame. Not to mention the other vampire courts, the (several) different types of werewolves, mummies, ghosts, spirits... basically, everything fantasy has created in one cohesive world, narrated in first person by a geek who quotes Star Wars every other sentence.
And never wears a hat, no matter what the cover artist wants you to think (it's become sort of a running joke)