Has anyone noticed Diane Capri's Hunting Jack Reacher series? This appears to be classic fanfic, but it's also selling and making lots of money, presumably. In this case she and Lee Child seem to be pals and there's no sign of a lawsuit, but could anyone get away with this, particularly in the U.S. with its ferocious intellectual property laws, written by and for MouseCorp? How is it decided what's plagiarism and what's fair use of a well-known scenario or character? "Discworld" with a capital may be copyright, but are a thousand other places and things?