I organize and straighten things in stores. Like turning jars so that all the labels are pointed the same direction, taking products that are in the wrong section where they came from, closing all the self-serve candy bins and making sure all the scoops are put back, etc...
Randomly saying stuff when I'm just sitting around, usually violent, disturbing things that would scare the crap out of people if they heard me. I can usually keep from saying it when people are around, but it's really hard to not say it, so I don't bother to stop if no one else is there.
Pointing in various odd ways at the computer screen whenever I send a command, test a newly compiled application, or other things like that, as though I'm trying to command a troop advancement, or use a spell. This one I really have no idea where it came from, and it just started in the last few years.
Cracking just about every joint in my body while I'm just sitting around. This one has some advantages, actually. Did you know that cracking your neck so loud that it can be heard across the room makes it certain that nobody will stand too close to you in line?
I have more, but I'm trying to break my habit of making long posts.

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