Let's talk about our favorite villians...

1) Hannibal Lecter (Hannibal)
2) The Joker (Batman)
3) Lord Sauron (Lord of the Rings)
4) John Malkovich (Con Air)
5) Anton Chigurh (No Country for Old Men)

Yup. The greatest bad guy of them all.

How about Nicholas Cage/John Travolta in Face/Off? Personally, I think they played their parts incredibly well. I also liked Travolta in Broken Arrow. He does a pretty convincing psychopath.

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The Lone Biker of the Apocalypse
"He was especially hard on the little things"

Can't really think of too many at the moment but my short list is:

1. Darth Vader
2. Kaiser Sozye
3. and more recently Anton Chigur off No Country For Old Men...he is god damn scary

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I have many others, but since this thread is a little old, I'll start with one unmentioned; the Captain (Sergi López) from Pan's Labyrinth. I think he'll retain his villainy for Posterity.

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I don't know if he's been mentioned already, but Michael Gambon's character in The Cook, the Thief, His Wife and Her Lover deserves a place on here. Peter Greenaway set out to create a character who could double as an index of the most unkind, ugly and disgusting traits a man could have. He's like an adult character from a Roald Dahl story, only worse.

In terms of charmingly despicable antagonists, Claire Quilty is one of Vladimir Nabokov's best creations, and Kubrick/Sellers turned him into a great movie villain as well. There's a corresponding character in Sean Penn's film, The Pledge. I don't want to give anything away, but the effect it has is creating an unsettling atmosphere, and it's a fantastic example of storytelling, if not a great specific villain you can put a face to (like Anthony Hopkins in Silence of the Lambs).

Batman Dark Knight,Batman-The Joker
Se7en-John Doe
The Silence Of The Lambs ,Hannibal,Red Dragon-Hannibal Lecter
Star Wars-Darth Vader

Irons was awesome in DIE HARD WITH A VENGENCE...the first DIE HARD villian to give Alan Rickman a run for his money.

1. Dark Knight-The Joker, as a long time comicbook reader Heath Ledger's performance was realisation of childhood dark fantasy.
2. No Country...-Anton Chigur, less human more force of nature.
3. Rounders- KGB, John Malkovich's character was more antagonist than villain but with what little screen time he was given, KGB proved to be a funny, intimidating and oddly honourable character.