Staples.

[Gizmo]

Mooncat, I used to do that as a kid - people would have conversations without even realising I was in the room and be shocked when they realised I was there. One time the youth leader almost forgot that I was in the car and needed taking home before he went home.

I can also apparently send out a "nope, not here to be served as a customer, just here to be in the way, ignore me" to shop staff (and teachers when I was in school).

[Mytical]

Mooncat, that makes sense! That would explain how I am able to 'sneak up' on people when I am 6'0" and was 305lbs at one time. Seriously, I would make people jump and ask "Where the heck did you come from!" how somebody can miss me is beyond me.