
I just love the way he and Casey Affleck successfully pulled off a massive hoax, lasting for two years.

Now Phoenix has apologised to Letterman. http://www.hellomagazine.com/celebrities-news-in-pics/23-09-2010/54750/
It was all part of him creating a character.
A "documentary" directed by Affleck shows the breakdown of the star and his descent into drug taking. When "I'm Still Here" first came out, it seems a lot of people were fooled.
Even the Sunday Times was unsure if it was a spoof, but the writer, a couple of weeks ago, revealed that Phoenix had slipped into the cinema where a preview was being shown and was laughing at all the amusing bits and looking pleased with the reception the film got.