Not worth it

A stranger walks up to an Egyptian man at the Cairo bazaar and offers to sell him contraband Viagra for 100 Egyptian pounds.

The Egyptian man says, "No, not worth it."

The stranger says, "How about 20?"

The Egyptian man says, "No, not worth it."

The stranger says, "How about 10?"

The Egyptian man says, "No, not worth it."

The stranger says, "Listen, these pills cost $10 each in the U.S. How can you say they're not worth it?"

The Egyptian man says, "Oh, the pills are worth it -- my wife isn't."