Amazon's Mechanical Turk - DataScoutingDataScouting

In other words, how to rent an army of slaves on demand.

Quoting from Amazon Web Services (emphasis mine):

Amazon Mechanical Turk is a marketplace for work that requires human intelligence. The Mechanical Turk web service enables companies to programmatically access this marketplace and a diverse, on-demand workforce. Developers can leverage this service to build human intelligence directly into their applications.
While computing technology continues to improve, there are still many things that human beings can do much more effectively than computers, such as identifying objects in a photo or video, performing data de-duplication, transcribing audio recordings or researching data details. Traditionally, tasks like this have been accomplished by hiring a large temporary workforce (which is time consuming, expensive and difficult to scale) or have gone undone.
Mechanical Turk aims to make accessing human intelligence simple, scalable, and cost-effective. Businesses or developers needing tasks done (called Human Intelligence Tasks or “HITs”) can use the robust Mechanical Turk APIs to access thousands of high quality, low cost, global, on-demand workers — and then programmatically integrate the results of that work directly into their business processes and systems. Mechanical Turk enables developers and businesses to achieve their goals more quickly and at a lower cost than was previously possible.

I can imagine requests being transparently serviced by an army of slaves somewhere in this world.
It always happened but now this army of slaves can be rented transparently, through a well defined API!