I've been reading about Paul Ekman and his creation: the FACS.  FACS was created to taxonomize the variety of human facial expressions, and it is really interesting.  I think that it could aid me in my sports betting, and prediction market in general, plus it would just be super interesting.  I'll admit I've been paying close attention to people's facial expressions for a long time, and the results are quite revealing.  This stuff will make a great addition to my library of knowledge.