Robert McKee talks about seeing himself in Adaptation over here. (Would've embedded it but I couldn't see how.) Here's a little texty excerpt:
Question: What was it like seeing yourself as a character in the film "Adaptation?"
Robert McKee: I took my son to a screening at Sony. And it's one thing... I've seen myself on screen many times because I've done umpteen TV series when I lived in England and interviews on TV, so it's not surprising, even though I myself played myself in another movie called, “20 Dates.” And so it wasn't that big a thing to see Brian Cox do me. But imagine what it would be like for a son to see his father portrayed in a major motion picture. And so he came out of the screening and I said, “Paul, what did you think?” And he said, “Dad, he nailed you.”
Thanks to David for the link!