Antolín Martínez used Subtitle Workshop, a free software for editing subtitles, and translations produced by volunteers or obtained from Google Translate, Babel Fish, InterTran to add closed captions in 26 languages for Charlie Chaplin's slient movie "The Kid". The movie, released in 1921, is in the public domain.
Here's what the author says about his idea: "This project shows how the power of the web 2.0 can be used by us – the ordinary people - to do nice and productive things together. It follows, in some sense, the altruists' lines that Chaplin referred in the last scene of his movie The great dictator. I hope that will be repeated by other people – and by me - to improve [the] great public domain films hosted at Google Video."
If your language is not yet available, you can translate the script and send it to Antolín here. An automated speech-to-text system and a translation engine, helped by some human contributors, could make a lot of videos accessible to a larger audience, even if the translation wouldn't be perfect.
About the movie. "The Kid was Charlie Chaplin's first full-length movie. It, more than anything else to that date, made Chaplin a living legend. It took over a year to produce, and was an incredible success for Chaplin." (archive.org)
Tip: You can change the language by clicking on the little arrow next to the "CC" logo from Google Video's player.
The movie: (also available at Google Video)