In my dissertation research I use Amazon Mechanical Turk to recruit participants for my experiments. Yesterday someone completed my experiment but Amazon would not let them complete the HIT, probably because they tried starting on one and switched to another (still not sure why). This meant that I had their data but couldn't pay them.

Amazon's thought of this. They have a great guide about how to pay for non-submitted HITs.

This is mostly here for me or folks who search for things when they get a little panicky about making sure people get their dues.