Performing human-subjects experiments on Amazon Mechanical Turk offers many benefits, including very low experiment costs, quick turn-around rates, and relatively simple approvals from human subjects boards. But you have to be careful to avoid bias and error.
PsiTurk is an open platform for conducting custom behvioral experiments on Amazon's Mechanical Turk.
It is intended to provide most of the backend machinery necessary to run your experiment. It uses AMT's External Question HIT type, meaning that you can collect data using any website. As long as you can turn your experiment into a website, you can run it with PsiTurk!