Billy Bob Thornton
The eccentric actor-turned-musician has talked about his OCD in 2004 with "Dateline"'s Ann Curry, saying it grew out of a difficult childhood filled with abuse.
One of his compulsions is "constantly doing mathematics," he said. "Certain numbers represent certain people. And I can't use that number in a certain circumstance. And then I have to use it in another circumstance."
"It exhausts you," he said about his disorder.
Obsession: Perfectionism and control