2001: A Space Odyssey
2001: A Space Odyssey (1968) is an American science fiction film, directed by Stanley Kubrick and based on the novel by Arthur C. Clarke. The film is widely considered to be Kubrick's masterpiece and it's certainly one of his most famous movies.
The mysterious film relies heavily on visual atmosphere and music (including György Ligeti) and lets the viewers draw their own conclusions. "2001" is well known for the groundbreaking visual effects and famous scenes such as the prehistoric ape throwing a bone in the air, followed by a camera shot of a space satellite. Another famous scene is the trip scene and the final scene where a gigantic foetus can be seen in space.
Zappa and 2001
An urban legend claims that the monolith used in 2001: A Space Oddysey can be seen in some scenes of Zappa's film 200 Motels (The Film). While a monolith can indeed be seen, it's actually not the same one used in Kubrick's film, as Kubrick had most of his models destroyed after 2001 was finished. On the same token Zappa didn't film in the same studio Kubrick filmed 2001 in either. 
The film is mentioned in the book Them Or Us.
"Not to be deterred, Frank then inquired if Lustig could get him the foetus used in the final scenes of Stanley Kubrick's 2001. "I want to put it on a string and swing it across the stage." But the idea had to be regretfully shelved as the foetus was apparently in America and safely out of the reach of the Mothers."
- Quoted from Frank Zappa. Reviled, Revered Mother Superior, Chris Welch, Melody Maker, 5 October 1968.