The BBC recently ran an article on phobias and invited readers to write in describing their own. No garden-variety fears of bugs or heights here:
Since I was little I have always had a fear of buttons - not buttons on clothes but loose ones that are either on the floor or if I am rummaging around in a drawer and come across one I freak out and can't even touch it. I have since met two other people that have the same phobia - at least I am not the only one.