Howard Hughes' court hearing at the end. I'm not sure if the real Howard had as spectacular a hearing as in the movie.
Actually, he did. Some of the quotes (like the one that includes "I will leave this country and never come back—and I mean it!") come directly from the transcript of the hearing. Further proof that Howard was basically a moment of awesome incarnate.
One-Scene WonderErrol Flynn starting a fight at a party. He steals a man's chair and the man throws a snowball at him in retaliation. Words are exchanged and the man calls him a limey bastard. Flynn corrects him - hes a Tazmanian bastard, thank you very much - then punches him down. When the man gets up and comes after him he knocks him down again, despite being held back and having another man between them.
Hughes calling out the Hepburns for talking a big game about socialism when they have a ton of money themselves.
Hughes in a plane filming a dogfight, and simply pulling out another camera when his zeal for a closeup gets his first one destroyed.
Hughes' extremely violent plane crash, which he survives and escapes despite his massive injuries (including his ribcage being crushed, pushing his heart to the right side of his chest). He is found by a good samaritan, asking who he is. He spits out "I'm Howard Hughes. The Aviator."