Discounting your choices, of which Stalker is fantastic.
1. Silent Running
2. Goke: Body Snatcher From Hell (it is insane)
3. The Quatermass Xperiment
1. Stalker
2. 2001
3. Akira
1. Wall-E
2. Mad Max
3. Ghost in the Shell
…yikes, 2 animated features.
No one for A Clockwork Orange? I haven’t seen the film myself but I was expecting it to be a top runner
1. Metropolis
2. Blade Runner
3. Children of Men
1. Brazil
2. 12 Monkeys
3. THX 1138
(as Blade Runner was already mentioned)
1. 2001: A Space Odyssey
2. Star Wars: The Empire Strikes Back
3. Alien
(as Blade Runner was already mentioned)
It’s perfectly ok to pick a film that somebody’s already picked. Just pick what you think’s the best.
1. Blade Runner
2. Brazil
3. The Thing
1. 2001: A Space Odyssey
2. Blade Runner
3. Empire Strikes Back
For me, there will never be a better decade than the 1950’s for strange and wonderful science fiction films. They are steeped in the paranoia that so predominated that period. Flying saucers, funny-looking space creatures, giant insects, the blob – what’s not to like??? So, here are my three picks from that decade:

Forbidden Planet

Invaders from Mars (1953 version)

Invasion of the Body Snatchers (1956 version)
Sure, films like 2001 and Stalker are stand-outs, but, for me (being a bit of a contrarian, here), they are so much more than s-f films (as is Solaris) – so I’ll stick to ‘classic’ fare.
1. Minority Report
2. Blade Runner
3. 2001: A Space Odyssey
I know my love of Minority Report isn’t typical, but I honestly think it is the perfect combination of sci-fi’s best elements: fantastic world building, cutting edge technology, socio-philosophical quandaries, and personal introspection.
I’m not putting Star Wars on here because I honesty don’t consider it a science fiction film. It’s space opera/fantasy. If it was on here, it’d easily be my number 1.
1. Blade Runner
2. 2001: A Space Odyssey
3. A Clockwork Orange.
1. Blade Runner
2. The Fountain
3. Children of Men
1) Blade Runner (the Final Cut)
2) The Element of Crime – not sure if it can be classified as sci-fi, though I’ve heard it has been here and there.
3) The Sacrifice – not really sci-fi entirely but I enjoy it quite a bit more over Stalker.
to charles deckert- I definitely wouldn’t put Element of Crime or The Sacrifice in sci-fi, not even with stretching
Videodrome
Blade Runner
World on a Wire
Normally I don’t do the “My favorites were already listed so I won’t list those again” thing but you know what? Now I will.
1) Tetsuo: the Iron Man
2) Videodrome
3) Another Earth
—PolarisDiB
1) Blade Runner
2) Solaris (ummm. yeah. not Soderberg’s. did I need to say that?)
3) The Time Machine (1960)
edited mine to include Videodrome, thanks DiB. Wasn’t sure if it’d count, but since you listed it i’m going to as well since i wanted to in the first place
Uh, well, I’m in Firefox so I can’t edit, so oh well to previously unstated movies. If Scampi doesn’t consider this cheating, replace Videodrome with Born in Flames.
—DiB
Ikarie XB-1
Time Masters
The War Game
Kudos to Oxy for mentioning Forbidden Planet, one of my childhood favorites that still holds up.
There have been many greats mentioned here so I’ll throw out three that haven’t.
Primer
Altered States
La Jetee
La Jetee
Stalker
Tetsuo the Iron Man
I’m liking these last two ^ sets of three. Funnily enough I’ve been meaning to re-watch Altered States for ages now, just never got round to it. Primer is fantastic – one of the few films I’ve watched then immediately re-watched as soon as it finished. And Tetsuo – that brings back really crazy memories.
1. 2001: A Space Odyssey
2. Blade Runner
3. E.T.: The Extra Terrestrial
Pretty much 2 through 6 are about even in my ranking, so everything besides 2001 is just random. Could’ve easily put Stalker, Solaris, or A Clockwork Orange in top 3. Definately enjoy Forbidden Planet and Inavasion of the Body Snatchers, great, top notch 50’s sci-fi.
1. Stalker (Tarkovsky)
2. Blade Runner (Scott)
3. Solaris (Tarkovsky)
2001: A Space Odyssey
A Clockwork Orange
The Empire Strikes Back
1. Sleeper
2. The Trollenberg Terror
3. Behemoth the Sea Monster
special mentions for Quatermass and the Pit and The War of the Worlds (1953 version, of course)
Scampi
Today I was watching the bonus features disc of Ridley Scott’s Alien – a fascinating behind the scenes documentary which runs almost 3 hours, and it really put me in the mood for re-watching the film again. It also got me to thinking about the best science fiction films. It’s a fairly straightforward exercise to cobble together a top ten in no particular order, but how about just the top 3? I really get the feeling there would be a solid consensus on this, though I’d be happy to be wrong.
So. A top 3 only – no sequels, trilogies or series counting as one choice etc. and no more than 3 films. Here’s mine.
1. 2001: A Space Odyssey
2. Stalker
3. Alien