Some pretty high-profile performances of actual or fictional handicapped persons seem really phony to me, but some feel lived-in, thoughtful and completely believable. The first strike against high-profile portrayals of this kind is that they tend to be performed by very recognizable, often overly-familiar actors, Am I the only one who considers Dustin Hoffman's RAIN MAN to be incredibly self-conscious, overly-studied and show-offy? But, then, I am so familiar with Hoffman in his other, much more convincing character roles that his attempt to act the role of an autistic person just doesn't work for me. I found Tom Hulce's character in DOMINICK AND EUGENE much more satisfying, probably because he hadn't saturated the movie scene, and the film was not as slick. It just felt more genuine. I also had a problem with Sean Penn's I AM SAM character, for the same reasons I did not accept Hoffman's. Penn is, like Hoffman, a deliriously talented actor, but that does not necessarily a great mentally-challenged character make. Oscars are nonetheless won by roles like these, and the ultra-well-known keep accepting them, hoping for the gold, thinking they can outdo the rest, sometimes they do. Wanna see one that works so well that, had you not seen him in other roles, you would bet he was actually retarded? That would be, in his best performance even to this day (in my opinion), Leonardo DiCaprio's teenager in WHAT'S EATING GILBERT GRAPE? He, like Larry Drake's Benny in the L.A. LAW t.v. series, seems never for a second to be anything but the person the script calls for him to be; these were completely flawless, in-the-moment performances. And neither of them is played by an overly-familiar actor. Julie Christie was heartbreaking (as was Gordon Pinsent as her husband) in Sarah Polley's emotionally sympathetic AWAY FROM HER, which dealt with Alzheimer's disease. The same topic provided Dame Judi Dench a not-quite-as-effective turn in IRIS, with Jim Broadbent providing wonderful support. There are lots of others, some good, some terrible. I'd love to have other members list their picks.