In 2005, Jeremy Winterson bought a bootleg copy of Revenge of the Sith in Shanghai and noticed something wrong with the English subtitles.
The movie’s dialogue had been translated mechanically into Chinese and then translated back again into English, leaving it almost incomprehensible. (A similar disaster had befallen a Portuguese-French phrasebook in 1883.)
Fans replaced the movie’s original audio dialogue with voice actors reading the mistranslated subtitles, and the result is Star War the Third Gathers: Backstroke of the West (highlights above).