Biggest Oscar Snubs or Nominees That Should Have Won

[Atreyu]

Three that come to mind.
1) I think Paul Giamatti should have been nominated over Thomas Hayden Church for Sideweays and he should have won
2) I still think Robert Downey Jr's performance in Chaplin was more deserving than Al Pacino's in Scent Of A Woman
3) I think Tom Cruises performance in Rain Man deserved at least a nomination because his character went from hating his brother at the beginning of the film to genuinely loving and wanting to take care of him by the end. A much harder feat to pull off tham Hoffman's one note chracter.