There is a writing term called "a talking head" which describes a character that the author drops into the story to dispense vital information to the main character at just the right moments. They are usually short lived and seem to come out of no where. (Sci-Fi original moves are very guilty of this). In general we are warned not to use them, but Jim Butcher looked the elements of style right in the face and said, "I'll do whatever I want to do." And he created the most beloved talking head, ever. Hear Jim Butcher explain how he came up with the character Bob. This is at a book signing for his new book, Turn Coat, in Omaha, NE on April 9, 2009.