Should've been Oscars:
Sean Penn - I Am Sam (Actor)
Sean Penn - 21 Grams (Actor)
Sean Penn - Sweet and Lowdown (Actor)
Sean Penn - Dead Man Walking (Supporting Actor)
Sean Penn - Carlito's Way (Supporting Actor)
Slightly one-sided I suppose
but in Scorcese-like fashion, they gave him an Oscar for Mystic River, and his performance, although good, doesn't come close to I Am Sam. He was beaten to an Oscar that year by Denzel Washington for Training Day
Watch the two films - make up your own mind
If anyone hasn't seen I Am Sam, then it's "Rain Man" meets "One Flew Over the Cuckoo's Nest" type film - would recommend to anyone, but make sure you've got a box of tissues ready for moppin up the tears