When making a top 30 list of anything, I think that it is wisest to begin with the classics; those that set the standards. It wouldn’t make sense to make number one something that was released just last week.
I went to Wikipedia to look for the true definition of science fiction. On my terms, I am describing it as a story with the following credentials:
1. Technology highly influences the plot and characters
2. Intricate scientific experiments take place
3. A world where science combines with imagination
4. Alien invasion / Human invasion (humans visiting a world unlike their own)
5. Excluding comic book super-heros (sorry X-Men, Spiderman, and Superman) and cartoons/animation (I love you Wall-E)
I used a basic list of “sci-fi” movies listed by decades in Wikipedia. Unfortunately I did not agree with some of the movies I found there. As a result of this, I have added some of the movies that I have seen, that I consider science fiction. With enough blabber, I introduce to you… my countdown of the top 30 science fiction movies. (For a more concise list without the explanation, scroll to the bottom of the post)

30. The Matrix - 1999
As much as I wanted to avoid putting this one on the list, I felt I was obliged to. The Matrix is the first of the trilogy. It made martial arts look cooler than it already was. For most people this was a modern take on the Bible, with references of the “one” and the “prophecy.” The Matrix is an interesting interpretation of the world and society and how technology affects us on a daily basis. I think it was only fair to start the countdown with this one.

29. Minority Report - 2002
Yes… it’s Tom Cruise. What’s the big deal? I thought Minority Report was a great movie. It has somewhat of a Logan’s Run vibe. This movie keeps you on your feet; a great example of science fiction.

28. A.I. Artificial Intelligence - 2001
Okay. Steven Spielberg again, but we all know that Steven’s forte is science fiction. I loved A.I. when it was first released. I thought it was an excellent film, not only was there technology, but there was heart. It was a film that was full of warmth, which can so easily be lost in this genre.

27. Earth vs. the Spider - 1958
I’m sure most of my readers are wondering just what this movie is. This is one in a long line of “creature” films mostly released during the 1950s. What exactly made these so popular? Well, just imagine a giant spider attacking your city, then you might understand.

26. The Deadly Mantis - 1957
Another creature film. Brace yourself, there’s more where these came from. But come on… a mantis? There’s no way I was going to leave this one out of the list.

25. Men in Black - 1997
Although this is one that most would not consider a “cinematic masterpiece,” I have to say that this film never gets old. I know everyone would like to wear a black suit, specially if it means being part of a secret service that keeps alien inhabitance on Earth under wraps.

24. Sunshine - 2007
A film that went somewhat unnoticed in my opinion. I am a fan of Danny Boyle’s work. The reason I picked this movie to be on the list, was not only because it dealt with outer space, but because I felt there was a certain depth to it. There were a few scenes from this movie that have stuck with me. I think to fully understand it, you have to understand Danny Boyle and you have to watch the film for yourself.

23. Star Wars I-III - 1999, 2002, 2005
Star Wars is my best friend.

22. Hitchhiker’s Guide to the Galaxy - 2005
Another amazing film that I think could have gotten more glory than it received. This is an intellectual comedy where nothing makes sense and everything makes sense. If you’ve read the book, you’ll love it more. Thank you Douglas Adams.

21. Transformers - 2007
Amazing special effects! I was unsure about seeing the movie at first, but after I walked out, I was definitely blown away. This was just a fun film all around!

20. Them! - 1954
One of the first of the creature films. Them! definitely would have to be my favorite of these movies. I could watch this movie over and over again. I mean ants are a nuisance just by being tiny, imagine if they were gigantic… and there was an army of them!

19. Alien - 1979
I had to put this one or everyone would stop being my friend. Alien, true science fiction at its best. If you haven’t seen Alien, you have no idea what science fiction is. It was either this Sigourney Weaver movie or Galaxy Quest. And as much as I personally love Galaxy Quest, I knew that people would protest; even silently behind their computer screens.

18. The Invisible Man - 1933
Although I debated about this movie, since most people know the book, not the film, I decided to add it to the list anyway. I was a little bit skeptical about it. I’m not sure if it’s full blown science fiction, but it is debatable considering the scientific fraction of it.

17. Logan’s Run - 1976
One of my favorites. It’s a long movie, but worth it for the end. Logan’s Run, a society where there are no elderly. No wrinkles, no beards. What a world, but what happens when it’s your time to leave? More than anything it’s the story that intrigues me.

16. The Fly - 1958
No no… there is no Jeff Goldblum, but don’t worry, I’m sure he’s in this list somewhere. Here lies the original movie, The Fly. A man experiments with a teleporting device only to turn into half of a fly. You’ll have to hunt down this film to see what happens.

15. The Fifth Element - 1997
Bruce Willis!!!! Okay okay, settle down. This has to be one of my favorites. This is one funny movie. Who hasn’t seen the Fifth Element? Well, go watch it!

13. The War of the Worlds - 1953 and 2005
Here, I have to give credit to both the original of 1953 and the remake in 2005. I enjoyed both films, and the classic novel by H. G. Wells. This is a great story, some might even say timeless (that is until aliens really do attack us). I don’t think this particular story will ever lose its touch.

14. Ghostbusters - 1984
Well, I thought it was a good pick.

12. Gojira (Godzilla) - 1954
The original Godzilla. Yay to the Japanese who gave us the knowledge of this creature’s existence; this menace to the city. Also thank you for providing the inspiration for the short film Bambi Meets Godzilla created by Marv Newland.

11. The Time Machine - 1960 and 2002
Another H. G. Wells classic. I enjoy both the original from 1960 and the newest update of 2002. Although I felt that the critics were a little harsh with the 2002 one, I still enjoy it. I think this is a very interesting story of time and how we evolve. Great book as well.

10. King Kong - 1933, 1976, and 2005
Although this kind of enters into a more “monster” movie, I think that it is science fiction set forth by the credentials I presented in number 4: Human invasion. A group of people enter this unknown and somewhat prehistoric island for very separate reasons only to find a giant ape dominating the island. One of my favorite movies P2k is the remake (2005) with wonderful actors. The movie lasts about 3 hours, but I could watch it over and over and never tire of it. I think it’s a masterpiece.

9. The Day the Earth Stood Still - 1951
By now, I think that mostly everyone is finding out about this movie released in the 50s because of the soon-to-be-released remake due this year (2008) with Keanu Reeves. I for one, have been a huge fan of the original since the first day that I saw it. Since then, I have seen it a countless number of times. I love, love, love this one.

8. 2001: A Space Odyssey - 1968
Stanley Kubrick.

7. E.T. the Extra-Terrestrial - 1982
20 years later, E.T. is still the lovable alien he was when he was first introduced to the world. His relationship with Elliott is the thing that really keeps this movie alive.

6. Jurassic Park - 1993
Ah, so here’s Jeff Goldblum. The first in the series. Playing the role of a god with the use of science; an amazing example of science fiction. Besides, dinosaurs are fun.

5. Back to the Future - 1985
Doc is awesome. Not quite The Time Machine, but come on… how weird is it to meet up with your mom when she’s the same age as you?

4. Planet of the Apes - 1968
The original Planet of the Apes of 1968. The one that started the sequels and the TV series. I have seen this movie so many times, I can recite it in my sleep. An upside-down civilization where ape has evolved from man and dominates the planet. Which planet? I suggest watching the movie.

3. Close Encounters of the Third Kind - 1977
Richard Dreyfuss is amazing. The best thing about this alien invasion movie is that you never actually get to see the aliens until the very end, and barely. The movie mostly focuses on the human mind and it’s an interpretation on how we as a society might react to finding out that there is another life form aside from our own.

2. Blade Runner - 1982
A very… very interesting story.

1. Star Wars IV-VI - 1977
Yay!!! Number one!!! I’d have to say that Star Wars the original and first of the series, Episode IV, is amazing. Thereafter enters V and VI. Like I said, Star Wars is my best buddy.
The List
30. The Matrix - 1999
29. Minority Report - 2002
28. A.I. Artificial Intelligence - 2001
27. Earth vs. the Spider - 1958
26. The Deadly Mantis - 1957
25. Men in Black - 1997
24. Sunshine - 2007
23. Star Wars 1-3 - 1999, 2002, 2005
22. Hitchhiker’s Guide to the Galaxy - 2005
21. Transformers - 2007
20. Them! - 1954
19. Alien - 1979
18. The Invisible Man - 1933
17. Logan’s Run - 1976
16. The Fly - 1958
15. The Fifth Element - 1997
13. The War of the Worlds - 1953 and 2005
14. Ghostbusters - 1984
12. Gojira (Godzilla) - 1954
11. The Time Machine - 1960 and 2002
10. King Kong - 1933, 1976, and 2005
9. The Day the Earth Stood Still - 1951
8. 2001: a space odyssey - 1968
7. E.T. the Extra-Terrestrial - 1982
6. Jurassic Park - 1993
5. Back to the Future - 1985
4. Planet of the Apes - 1968
3. Close Encounters of the Third Kind - 1977
2. Blade Runner - 1982
1. Star Wars 4-6 - 1977
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