Kurtwood Smith as Clarence Boddicker in Robocop, and Sam Neill's Damien Thorn in The Omen III: The Final Conflict.
BobDobolina said:
Amon Goeth (Schindler's List): Hans Landa from Inglourious Basterds is a more popular choice for "best villains" list, because he's comfortably fictional and there aren't real hordes of crypto-neo-nazis and witless goth girls idolizing him on YouTube. But the fact that he was based on a real guy makes him a million times more chilling.
Ralph Fiennes was so good, in fact, that reportedly several survivors who met him on the set were terrorized almost to the point of panic when they saw him in SS uniform, because he resembled Amon Goeth almost like a twin. He and the filming team had to reassure them, and actually tell them that he wasn't Goeth, but just an actor playing him.
I cannot blame them, however. Fiennes' Goeth was an angel of mercy compared to real-life Goeth, who was a sadistic, sociopathic monster. What Fiennes did in Schindler's List was nothing compared to things the real Goeth did while in command.