When I first read about Amazon's mechanical turk. I hadn't realized that this wasn't just human data mining for Amazon properties but in fact was an open system (according to techcrunch). That's great! I remember reading (but not where, so the story may be apocryphal) about chinese typing factories that did manual OCR for western companies. The way they dealt with errors was by simply doing all the typing in triplicate and voting - which reduced the error rate enormously.
Now everyone can play - Amazon has effectively set up an open market for routine office/terminal work. Whether this would make sense for anyone not in Eastern Europe or Asia I don't know. It might make sense for teenagers or kids as a game-like activity that is also economically rewarding.
Actually, I remember having a problem with data washing something like a quarter million phone numbers. We had to come up with a cheap way to reformat all kinds of strange ways people write their phonenumbers into ISO format. We used to dream of an making an online service where would get people to do the work as a recreational activity - but this is much better. If I had that problem again I would experiment with sending it to the Turk.