At his blog, John Hawks considers an approach that some researchers advocate for finding anonymous research subjects: signing them up at Mechanical Turk, Amazon's virtual marketplace where organizations can pay people to do various tasks. "Some psychologists have found an unexpected source of research subjects in the Mechanical Turk. It's a whole lot cheaper to pay anonymous users for small online tasks than to find subjects and pay them to come into a lab for an afternoon," Hawks writes. Of course, there's the IRB challenge, though he notes that some IRBs treat subjects found this way as exempt. "It seems like a 'new frontier' in terms of rapidly profiling and developing experiments," he adds. Any chance this will spill over from psychology to biomedical research?