Obsessive-Compulsive Disorder? Tell him his hands are dirty.

Tourettes? Ask him to curse - twice.

Attention-Deficit-Disorder? After everything s/he says, ask "What?"

Schitzophrenia? Ask, "Do you hear something?"

Multiple Personalities? Always assign *them* three projects concurrently.

Anorexia? Ask if they've put on a few pounds.

Bulemia? Give them a gift of a plastic finger.

Suicidal? Tell them they look "run down."

Masochistic? Tell them you love their scars.

Sadistic? Show them an unrelated scar on your body and ask "remember this?"

General disorientation? Ask them to proofread a paper with the pages stapled in backwards order.