Find out what people are really thinking!
I remember a show came out a few years ago about a policeman who could solve crimes because he had the ability to detect 'micro expressions'. He would film criminals being interrogated, then watch the footage, frame by frame, to catch the involuntary, fleeting expressions that would give away their true feelings. I was thinking about it again recently (turns out it was called Lie To Me) – and realised it's based on a real thing that's actually quite widely accepted!
Microexpressions only last up to one fifteenth of a second, but there are a limited number of them and we can all learn to get better at spotting them. They were developed by a guy called Paul Ekman, who believes there are six universal emotions most commonly suppressed into these fleeeting expressions: disgust, anger, fear, sadness, happiness, and surprise.
Have a look at this fascinating film by Michael Simon Toon – if you have the ability to slow down footage you can spot some great micro expressions much more easily.