The other day, Gimli lay in the doorway to the office and fell asleep. He was in such a deep sleep that he didn't hear me turn around in my chair, (it was a small miracle I actually made no noise!), and turn to look at him.
After a few seconds, he woke up, saw me staring at him and he proceeded to look around as if a) he'd done something wrong or b) there was a monster behind him about ready to pounce.
I didn't have a camera nearby so you'll have to settle for this video, which is quite close to Gimli's facial expression: