Here is my top 50 list.
If Alien is going to be classed more horror than Sci-Fi, I hope the hounds of Dem will be unleashed if anyone includes - Event Horizon or Carpenter's 'The Thing' as they both have far more horror in them than sci-fi.
I'm also looking forward to learning about more films from you all, this thread is great.
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Vipp's Top 50 Sci-Fi Films.
01. Fantastic Planet (1973)
02. The Day the Earth Stood Still (1951)
03. Invasion of the Body Snatchers (1978)
04. The Thing from another World (1951)
05. A Boy and his Dog (1975)
06. Logan’s Run (1976)
07. Robocop
08. Forbidden Planet (1956)
09. Soylent Green (1973)
10. The Fly (1986)
11. The Incredible shrinking man (1957)
12. Invasion of the Body Snatchers (1956)
13. The Day of the Triffids (1962/3)
14. 2001: A Space Odyssey
15. The War of the Worlds (1953)
16. The Brain that wouldn’t Die (1962)
17. The Matrix
18. Westworld (1973)
19. Terminator 2: Judgement Day (1991)
20. Earth VS The flying saucers (1956)
21. They Live (1988)
22. The Minority Report (2002)
23. Quatermass and the Pit (1968)
24. Total Recall (1990)
25. Serenity (2005)
26. Moon (2009)
27. Silent Running (1972)
28. The Quiet Earth (1985)
29. The Omega Man (1971)
30. Starship Troopers
31. The Terminator (1984)
32. Robocop 2
33. Jurassic Park
34. The Fly (1958)
35. The Abyss (1989)
36. WALL-E (2008)
37. TRON (1982)
38. The Fifth Element
39. Star Wars (1977)
40. Mad Max 2: Road Warrior
41. Brazil (1985)
42. Tetsuo: The Iron Man (1989)
43. The Island (2005)
44. Children of Men (2006)
45. Equilibrium (2002)
46. Atolladero (1995)
47. Aliens (1986)
48. Solaris (2002)
49. Sunshine (2007)
50. Back to the Future