Mostly we think of this as it relates to English-speaking fansubbers working on Japanese anime, but here's a tale of the reverse: a guy in Japan who fansubbed an American movie and released it via BitTorrent. 33-year-old Kazushi Hirata fansubbed the Angelina Jolie flick Wanted, released it prior to its Japanese theatrical release, and was arrested in September.
He plead guilty in November and was sentenced yesterday: he'll spend two years in prison and be suspended for three years after that (I'm guessing that's like parole?). And it could have been worse: he could have gotten as many as 10 years in prison with a $95,000 fine.
Now, American movies reach a much wider audience in Japan than anime reaches in the US-- which means the US (and Japanese) anime industry depends even more on each and every individual sale than American movie companies. Just food for thought.