I had seen this go up a long time ago and thought it was an interesting concept. I was reading a blog recently that mentioned it again under another context and it reminded me of the service. Amazon's Mechanical Turk is essentially a work-for-hire program for very small units of work, labelled Human Intelligence Tasks or HITS. From the employee side of things it allows for a great deal of flexibility. One can pick up the jobs on the fly that are easy for them do and provide as much variety as one would like to feed their ADD disorder. From an employer side of things, crowd-sourcing mundane tasks that can be split into simple units of work could result in greater throughput. However, my opinion on the matter, having never actually participated in the service, is that the overhead of managing the tasks could outweight any benefit gained via the increased throughput.
Interesting none-the-less.