AFI's "10 Greatest Sci-Fi Films: The 50 Nominees"
The American Film Institute’s official 50 nominees for the Top 10 Science Fiction Films of All-Time (to be announced June 17, 2008)
"AFI defines “science fiction” as a genre that marries a scientific or technological premise with imaginative speculation."
"Whether it’s a flying saucer whirling through space or a gleaming city on a distant planet, at the core of all science fiction is the provocative question, “What if…?” Science fiction presents stories and situations that tap our brightest hopes and darkest fears about what might, one day, turn out to be true."
Check out all the entries from "AFI’s Top 10" here: http://www.listsofbests.com/list/55322/tagged_as?name=afi+top+10
In alphabetical order.