Greatest Sci-Fi movie ever?

Question

Im not letting anyone answer with any of the "Star Wars" films because that's an obvious choice...

So, excluding the "Star Wars" films, what is the greatest Sci-Fi movie ever?

Update:

Im for 2001: A Space Odyssey all the way. In my opinion, it's one of the greatest movies ever.

APC: I think I saw 'Them!' on AMC really late one time... Pretty interesting movie.

Answer 1

Favorite Answer

Not many people have heard of this movie, but Them is one of the best Sci Fi movies I ever saw.

http://en.wikipedia.org/wiki/Them_(1954_movie)

Answer 2

Some people will laugh at my answer but I loved Stargate when it came out and I loved most of the Stargate SG1 series as well.

Of recent films I thought Sunshine had an intersting concept.

Answer 3

I believe without any hesitation I would say 2001.

Way ahead of every known curve and one of the few science fiction films to bother to get the physics of weightlessness correct.

It's bold, beautiful, cryptic, epic and funny. How can you beat that.

Answer 4

Alien

Answer 5

In terms of high concepts, production values, and ahead of its time, hands down winner is Forbidden Planet

Answer 6

ive always liked BattleStar Galactica...

Answer 7

invasion of the body snatchers was good!