Amazon's Mechanical Turk pays people to perform tasks that computers can't easily do, such as fill out opinion surveys, transcribe audiotapes and see whether items for sale have been correctly "tagged," or classified. The Mechanical Turk for which the Web site was named was a 1700s and 1800s hoax in which a supposed machine played chess (the Turk actually concealed a human chess ace). Amazon started the site to find humans to help fix problems that its automated systems couldn't.
The Mechanical Turk is now used by an array of "requestors" who want people to help them with various small tasks.
The problem here is that the pay is often literally pennies -- sometimes just a single penny to perform a task that might take a few seconds or minutes. Only you can determine whether the time you spend is worth the payoff.