I nominate the classic movie The Day the Earth Stood Still, starring Michael Rennie and Patricia Neal, which is available on Netflix.
In 1995 The Day the Earth Stood Still was selected for preservation in the United States National Film Registry as "culturally, historically, or aesthetically significant".
The Day the Earth Stood Still also received recognition from the American Film Institute. In 2001, it was ranked number 82 on 100 Years...100 Thrills, a list of America's most heart-pounding films. It placed number 67 on a similar list 100 Years...100 Cheers, a list of America's most inspiring films. In June 2008, the American Film Institute revealed its "10 Top 10" — the best ten films in ten "classic" American film genres — after polling over 1,500 people from the creative community. The Day the Earth Stood Still was acknowledged as the fifth best film in the science fiction genre.
The film was also on the ballot for AFI's other lists including 100 Years...100 Movies, the tenth anniversary list, 100 Years...100 Heroes and Villains for Klaatu in the heroes category, 100 Years...100 Movie Quotes for the famous line "Gort! Klaatu barada nikto!", and AFI's 100 Years of Film Scores. In 2004, the film was selected by The New York Times as one of The Best 1000 Movies Ever Made.
I repeat for emphasis:
"The Day the Earth Stood Still was acknowledged as the fifth best film in the science fiction genre."
It's also the only movie I know of that had the balls to say "Stop obsessing about Communism, you childish jerks" at the height of the "Red Scare", and even cast a blacklisted "Communist sympathizer" in a major role.