Help name the 50 best sf films

John Scalzi (an amazing sf writer and the author of several great nonfic compendia of trivia) is doing a book on great sf films and he needs your help:

As some of you know, I'm currently writing The Rough Guide to Science Fiction Film, which will be a general overview of the history of Science Fiction in films, with chapters on some various themes (science in science fiction, SF film icons, crossover subgenres, etc) and so on. The heart of the book, however, will be the Science Fiction Film Canon: The 50 classic Science Fiction films. In my own brain, I see this list as the list of the most significant science fiction films, as opposed to the "best" or the most financially successful. This gives me latitude to, say, include films that are influential on science fiction filmmakers, but not necessarily the audience (or, vice versa, as the case may be).

(You rightly ask: And why do I get to choose the Science Fiction Film Canon? Well, because someone paid me to, basically. But also, I'm both a professional film critic of more than a dozen years standing, and I'm also a professional science fiction writer. If someone's going to compile this list, it might as well be me.)

I of course already have a preliminary list of 50 films ready to go. BUT! Even with my rather extensive knowledge of science fiction, film and science fiction films, I am more than willing to entertain the notion that my list has gaps: Films that should be on the list may not be there — films that I have on the list may not deserve to be there.

So, this is where you come in: Suggest me some science films (one or more, as many as you like) which you feel are especially significant. If you want to jot down a sentence or two as to why you think they're significant, that'd be swell (to be clear, any comments you make on films are for my personal edification — I won't cut and paste into the book. I do my own writing). Any films you might care to think of are appreciated…

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