Psych experiments that haven't been done?

An addendum to Kent's excellent psychology experiments series: what about the experiments that haven't been done? A few years back the British Psychological Society's Research Digest blog asked a number of psychologists, writers and scientists to chime in with their thoughts about what the best psychology experiments were that have never been done (and perhaps never can be). Contributors include Martin Seligman, Judith Rich Harris (The Nurture Assumption) and Vaughan Bell (of MindHacks). Here are some of their ideas:

* a real "Truman Show" experiment
* switching parents of children at birth (to test nature/nurture)
* taking brain scans of people *as* they die

See the full list of 13 here. Maybe you can find a few to have your students attempt to come up with some operational definitions for, or even find an actual way to do some of these?