Interesting fact:

While certain fears like arachnophobia or claustrophobia are common and familiar, there are some that are more exotic: Coulrophobia is a fear of clowns. Arithmophobes are afraid of numbers, and to sufferers of Koumpounophobia, buttons are nightmarishly scary. Now, these phobias may sound weird or even funny, but keep in mind that they cause severe fright in their respective sufferers.