After everything he says, say, "And how does that make you feel?"

Repeatedly tell him to look at the ceiling. When he finally does,
repeatedly tell him to look at the chair. When he finally does,
repeatedly tell him to look at the desk, etc...

Refuse to cooperate unless he trades his pants.

Point at random things and say, "Where did you get that?"

Try to talk him into sitting on the floor.

Tell him you think his secretary is really a man.

Take random objects in his office and glue them to the floor.

Bring pots and pans and bang them together when he asks a question you don't like.

Complain that his chair looks more comfortable.

Sit underneath your chair.