I think
The Matrix trilogy is one of the very best because of almost everything! It had excellent music, great story, great casting, excellent visual effects and so on. The things I liked most about this movie are the idea first of all, after watching it I was terrified of what if it is true! And the philosophical issues that were mentioned, the character and dialogues of Agent Smith.
The other is
2001: A Space Odyssey ( It's surprising how no one has mentioned it yet) it is one of the best sci-fi movies I've ever seen. It has an interesting story, good music, I would describe it as hypnotic, and the visual effects are unbelievable for a movie made in the 60's.
And of course
AI: Artificial Intelligence by Stephan Spielberg. When I first saw this one, I was I think 7 or 8 years old and I was stunned, it was very emotional and I saw it again a couple of days ago and again I almost cried!
Pink Floyd: The Wall, well first of all there's the legendary Pink Floyd music, the anti-war theme, nice visual effects , and it was a deep movie
Dead Poets Society The story is just amazing, I wish all teachers were forced to watch this movie.
Lord of The Rings trilogy Based on the story by J.R.R. Tolkien there is no need to talk about the story, it had excellent music and very good acting.
And the movie
Pi(Pi as in the famous Pi number) It is about a young mathematician looking for a pattern in the stock market, one day his computer prints out some apparently random string of digits and crashes...(watch the film
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), the music is by Clint Mansell, it's great. Although produced in 1998 it is in black and white, which is, in my opinion, a good thing. And I like the references made to mathematics in the film and how it is said by the protagonist that nature is made up of numbers and there surly is a pattern in it.
And some other movies I like are: I Robot, V for Vendetta, K19: The Widowmaker, Bladerunner, The Bourne Identity and The Bourne Ultimatum, The Shining, The Red Planet, Sunshine, The Illusionist, The Eternal Sunshine of the Spotless Mind, The Secret Window, The Truman Show and some others that I don't remember right now(I might right about them later)
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.