Amazon has released a beta of the Mechanical Turk. It allows a program to programatically ask a question to a human and wait for the answer. Here's an example (copied from Google Blogoscoped):

read (photo);
photoContainsHuman = callMechanicalTurk(photo);
if (photoContainsHuman == TRUE) {
   acceptPhoto;
}
else {
   rejectPhoto;
}

This is really like the Matrix except that the humans get paid a little bit of money (but in the end that's close to getting fed) and it's other humans that controlling the programs... until we have web services using other web services using the Mechanical Turk. Then who's controlling who is going to be hard to decide :-)

Source: Google Blogoscoped.