I have never been a big fan of online quizes. I don't care what South Park character I most closely represent, I know what my IQ is, I already found my perfect match (my girlfriend), and I don't need any quiz to tell me I am a jack ass, enough people already tell me that. However, I ran across an online quiz published by BBC Science & Nature called Spot The Fake Smile.
The quiz is "based on research by Professor Paul Ekman, a psychologist at the University of California" and asks you to, what else, spot which smiles are fake. It is composed of 20 questions, each question has a short video clip showing a person to smile and then asks you to determine if the smile was genuine or not.
Now I'm no Hellmuth, but I ended up getting 19 out of the 20 correct. Still, if I was sitting at the table, that one mis-read would have been the big pot of the night with my luck and I would have gotten taken for a ride. Then again, most times you mis-read a person the pot ends up being pretty big, or bigger than it should have been, and you always get taken for a ride so I guess there is nothing special there.
At any rate, the quiz is based on Ekman and Wallace V. Friesen's Facial Action Coding System (FACS) which is used for measuring and describing facial behaviors. The goal behind the categorization of facial movements is to try to "get a read" on a person by what their face is saying. Granted the study was not specifically intended for poker, but neither was statistics, that doesn't mean it can't play a large, positive role in your game. If you are looking for more information on FACS, you can find some more information here but the real jewl there is the sample of the FACS Manual. I don't know if the entire thing is worth the money they are asking for it, but it sounds pretty interesting or at least like something Mike Caro would read.