1) When I have to cut up my food with a fork and knife, I cut it all up at one time into bite-size chunks and only begin to eat after I'm done cutting.
2) If I'm drinking from a small bottle with a replaceable screwtop -- soda, bottled water, frappucino, what have you -- I replace the top after every drink, so when I drink again I need to take the top off again.
I don't know why I do these things, but I do, and I honestly never thought about them until they were called to my attention. No compulsion involved, but for whatever reason they're part of my default setting. It's odd, the little things that sneak up on you.