[Lord Chane]

1. Forbidden Planet. Cutting edge effects for its time, good story, and you can see the impact it had in so many other productions. The Jupiter 2 in Lost in Space was patterned after the C57D, the Robot was a knock-off of Robby, even Babylon 5 had an homage to FP in the shots of the "great machine". And it was the first really great sci-fi movie I ever saw.

2. Blade Runner, the original Version with Harrison Ford's narration. The vision of the future is so spectacular. Harrison Ford is great. Good story, good acting, incredible atmosphere.

3. Aliens. Great plot, good acting, engaging characters, a little humor "Somebody wake Hicks up!", a great foe, lots of action, some sharp looking military technology, etc. Absolutely top notch.

Here are some other good sci-fi movies (IMHO) that I don't think I saw mentioned in this thread.

1. The Omega Man. I was about 14 when this first came out and after seeing it I thought it'd be so cool to be the Last man on Earth.

2. Cyborg 2087. Another sci-fi movie with Michael Rennie, who was the star of The Day the Earth Stood Still. It's about a Cyborg sent to the past to stop a scientist from inventing some device (don't remember what) that'll affect the future. Something of a precursor to The Terminator.

3. The Time Machine. The original Version from the early 60's.

4. Fantastic Voyage. Something of a unique plot. Suffered from some severe plot flaws but a very good movie over all.

5. It Came From Outer Space. Another movie from the 50's. The first movie I can think of where the alien's hadn't come to take over Earth. The aliens here were just trying to get home.

6. Outland. Sean Connery. Something of a "High Noon" set in space.