I would say The Thing, but then I never saw the original. Be amazed if it was better though.
Actually, the Howard Hawks 50's version is a good film, although nothing like John Carpenter's - the thing is basically like Frankenstein's monster, with no shape shifting or duplication. The film is also a cold war allegory. Nevertheless, it is quite creepy in places.
The opening credits of JC's version are a homage to the earlier film.
I would recommend the short story they are based on, Who Goes There? by John W. Campbell, Jr. Some critics slag off the JC film, but probably aren't familiar with the original story. You can read it online here. The Carpenter film isn't really a remake.
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