Fidgeting

Often when I'm on the phone or in a long lecture, I find myself fidgeting with something. Yesterday it was a disposable roll of double-sided scotch tape. Few of my plastic pen caps have pocket clips any more, as I have absent-mindedly twisted them off. I have no straight paper clips.

Doing this helps me focus. As long as it's not a particularly thought-provoking fidgeting object, using my fingers for something trivial provides just enough stimulation to focus my other senses on the lecturer or the phone conversation. Doodling serves the same purpose. Looking back on my old class notebooks, there seems to be a strong correlation between the number of doodles and the interest that I had in the class. The type of doodle also seems to matter; more abstract or thoughtless drawings (an array of cross-hatching, squiggles along the boarder of the page) tend to happen when I am interested in something but slightly too restless to just sit still and listen.

I frequently notice other people doing this too. What are some of your favorite mindless fidgets? Is this a bad habit, a good tool for focusing, or just an inescapable part of human nature?