Dream Teacher

The Dream Teacher was a teacher that appeared in Fry's dream in A Fishful of Dollars. Fry dreamt that he was about to take the final for a class he didn't know, and was shocked to find that it was in Ancient Egyptian Algebra. To make his nightmare worse, he was in his underpants. The teacher then informed Fry about Lightspeed Briefs, starting an advertisement.

Quotes

 * Dream Teacher: Mr. Fry! Are those your underpants?