I don't think i do the classic flapping motion with my hands up in the air... But when i'm stressed i sometimes move my hands down at my sides in different ways, sometimes a bit flappy. A newer one i've been doing when i'm nervous at work a lot is moving my fingers rapidly back and forth. I think the most noticeable and autistic-looking stim of mine is the rocking, which i've been doing for a long time, but has gotten more pronounced over the years. Most of my stims depend on the position i'm in, though... And some i'll do anytime, whether nervous or relaxed, and others i do more when nervous or frustrated. I usually rock when i'm sitting somewhere and not leaning on the back of the chair(like if i'm doing something at a table, on the computer, or whatever) and i'll do it no matter how i'm feeling. Right now i'm on my laptop and i'm leaning back in my chair, which is a recliner, and i have the foot rest part up... so i'm moving my left foot up and down(sort of foot-flapping, lol).. And i'm not nervous, i'm totally relaxed. Other things, like the hand movements i mentioned, i do more at work when i'm stressed. When i'm standing it's hard to rock, unless i'm leaning on something(and i do sometimes rock when i lean back on the table when i take a phone call or something), but i sometimes sway from side to side, shifting my weight from foot to foot. While walking i sometimes tap my fingers at my side.. And, i don't know if this would be considered a stim or what it is exactly, but at work i have a habit of tapping the shelves as i walk by(it kind of distracts me from all the people and stuff going on).