A phobia is an irrational fear. A lot of times the person with the phobia realizes just how irrational the fear is, but that doesn't change anything for him. You should never make fun of a person afflicted with a phobia, but you could use phobias to create an unforgettable character, one whose fear puts him or her in amusing situations.

This article talks about barophobia, batrachophobia, chaetophobia, optophobia, and phalangophobia.

Phalangophobia and Other Phobias