Favorite Science Fiction Movies

[Scifiguy]

I love Science Fiction, and there is no end to what I like in that subject area. But what is your top five Science Fiction movies and why? I have an endless list but if I had to name five which I am, then they would be. 

1. Star Wars the first one.
   
2. Star Trek the Wrath of Khan.
   
3. Close Encounters of the Third Kind.
   
4. Blade Runner the original one with Harrison Ford.
   
5. Heavy Metal the 1981 cartoon. Saw it at the drive in, and it blew my mind.
   

So what are yours?