Steven Jan Vander Ark, a huge fan of J.K. Rowling's Harry Potter series, thought it might merit a sort of reference book — a lexicon — for fans like him and new readers, to help them sort through the twists and turns of the magical tale. He spent seven years working on it, and Rowling sued him for its — some might say inevitable, even necessary — resemblance to the original books. Judge Robert P. Patterson Jr. of the Federal District Court in Manhattan agreed with Rowling, called it plagiarism, and sent Vander Ark and his lexicon packing. It's tricky. While a guide is something Vander Ark's fans (he has a website, the Harry Potter Lexicon) expressed a great need for, it's true, it wouldn't be successful without extensive borrowing from the series itself, in which words, locations, and much much more are straight from the mind of the author, Rowling, and as such, her intellectual property. In the end, the judge decided this passionate fan (who bears no ill-will to Rowling, calling it a legal dispute he "would rather... wasn't personal") is on the wrong side of the law. Which camp are you in?