Do you stare straight ahead at the doors? Down at your feet? At someone else's feet? Let your eyes wander around the walls, searching for something to read?
Do you make eye contact with other passengers or avoid it? Do you talk to them or keep quiet? Does it matter if you know them?
Do you keep your arms at your sides or folded in front of you?
Do you shift uncomfortably waiting to reach your floor?
Is your behavior any different on a subway train? In a waiting room?
Do your answers signify anything deeper about you? Or am I wasting your time even asking?