Memrise is an addictive game to learn languages and more. I've been playing it for a while now. You can score points in several ways, mostly by answering correctly.
Going through the courses I noticed a couple of weird courses, where the answers are just the same as the questions (e.g. 1 -> 1, 2 -> 2, 3 -> 3, ... 42 -> the meaning of life, 43 -> 43, ...). I also noticed that the points can be slightly addictive, I've used them to push myself to learn just a couple more Mandarin Hanzi every time. If you think that's silly, check the Memrise Leaderboard today, which is temporarily disabled "after extensive cheating has been brought to our attention, some of which has been slowing down the site for the whole community."
The cheating in question is that several members of the community appear to be using bots to accrue more points; others are using dummy courses with simple answers to rack up vast scores; and in one case we have evidence that a small army of children has been employed to exaggerate one individual's learning accomplishments. While we applaud the imagination and competitiveness of such cheats, we condemn their behaviour, which is unfair on everyone else in the community.
Note that these points have no monetary value whatsoever. Where there is monetary value we can expect things to be much worse. If you don't believe me, read Doctorow's FTW, it's science fiction but I'd be surprised if you deny the existence of game gold sweatshops after reading this.