You go into a store to purchase something. A salesperson comes over and asks you if you need help.
This person seems fairly agreeable. There's something, you're not quite sure what, about them that you like.
Unknown to you, they are imitating your head movements, your gestures, and some of the other body language you display. It's a studied phenomena, often referred to as the Chameleon effect.
Can it help three dimensional and computer generated beings become more successful salesmen? That's what they've been trying to find out at Stanford.