Chewing random objects, licking myself to stop blood flowing down my arm when I can't get something to soak it, and licking something to clean it. (for example, I drop my MP3 on the floor, to see the screen again I lick it - I don't even know how I manage it)
Did you ever believe any of those shock-out-of-a-habit things? (like, don't swallow chewing gum, it'll stick to your lungs)