Makeup Lamps tracks an actor's movements without using the facial markers common in motion capture, then it displays any color or texture the actor wants by adjusting the lighting. It can make someone appear older by creating "wrinkles" on their face, for example, or it can paint their face in creepy clown makeup, à la Heath Ledger in The Dark Knight. And all of it is done in real-time.
A similar technology was used earlier this year during Lady Gaga's performance at the Superbowl.