5. Lars Von Trier
Apparently referred to as 'The Punisher' in some parts, Lars von Trier is a self-confessed control freak and occasional depressive (he was going through a breakdown whilst shooting Antichrist, and almost didn't complete the film) who's happy to put his actors through hell.
Particularly if they're women: on Dancer in the Dark, the director was apparently so
cruel towards Bjork (purportedly in an effort to provoke the artist into giving a performance to his satisfaction) that she vowed never to act again.
Nicole Kidman, to whom Bjork had sent a letter encouraging her not to work with von Trier because he would "eat her soul," took long walks with von Trier on Dogville just to have long shouting matches with the director. She vowed never to work with him again.
Paul Bettany had a similar response, calling Dogville "a hideous experience...You're absolutely his puppet." It can't be easy to act as PR for von Trier, either, what with him publicly making comments about sympathising with Hitler and whatnot.