Actor George Clooney is a well-known prankster on movie sets. But one time his pranks backfired on him. He baked a number of cookies using rabbit droppings instead of chocolate chips. He brought them to the set of Ocean's Eleven and called them "vegan chocolate chip cookies". Actress Julia Roberts was warned about the cookies. She pretended to eat one and get sick and then hired a doctor to convince Clooney that she was suffering from tularemia or "rabbit fever". Clooney was so upset that he donated over $50,000 to the hospital she was being treated in before she let him in on the joke.