Tom Sawyer and social media

"Tom said to himself that it was not such a hollow world, after all. He had discovered a great law of human action, without knowing it – namely, that in order to make a man or a boy covet a thing, it is only necessary to make the thing difficult to attain."

Sounds awfully similar to Web 2.0's user driven content isn't it? Make up tasks, make users compete, and award them with badges, karma score or any other award that is vague enough to define and impossible to achieve.