Anakin Skywalker (from "The revenge of the sith") - INFP
Yoda (from "The revenge of the sith") - INfJ
Chancellor Palpatine (from "The revenge of the sith") - INTJ
Mace Windu (from "The revenge of the sith") - IsTJ
Obi Wan Kenobi (from "The revenge of the sith") - ENtP
I thought that Lex was an INTJ, being always alone and all....
I agree with the others' types, though.
He is a difficult blend.
Lex Luthor is a powerful contrast of external control (Lionel's influence) vs. struggling to achieve stability within himself (Alexander).
This dichotomy is so pronounced that I'd wager his "evil" behavior stems from his extroverted hemisphere overcoming his pensive introversion.
The truly evil Lex Luthor is profoundly E (See his presidential campaign for a Lucifer analogue). When Alexander wins, Lex fragments inward and his genius is channeled into an emotionally recuperative theater.
Either manifestation finds self-service as his greatest motivation; it depends if Lex retreats inward or soldiers outward to achieve this balance, in terms of how he pursues his goals.
Lex Luthor (Superman Returns)- INTJ
Superman / Clark Kent- ESFJ/ISFJ
Now things are messy. Wasn't it supposed to be the other way around? Lex from Smallville, INTJ.
And Lex from Superman Returns, ENTJ (he's always surrounded by people and in the beggining he was able to court and be some sort of gigolo to that old dying lady to get her fortune). Although an INTJ could also go through all that, it's not very likely.
I think i'll stick to Night's explanation of Lex's type in Smallville. Some sort of mix between ENTJ (being so straightforward and agressive with everyone) with INTJ (being a loner).