I was doubtful at first, because of the need for both a computer (and Internet connection) in a part of the world where 25 cents an hour would be a decent lower-middle-class income.

The World Bank has some information about countries with people living on $2 per day. (http://data.worldbank.org/indicator/SI.POV.2DAY)

Maybe there's a use for a "Fair Trade Mechanical Turk" - someone sets up an Internet work space for people in developing nations and FTMT sets minimum wages?

Just block first-world nations from accessing *.mturk.com, and problem solved.