You've been a server before, and never forgot the day somebody tipped you with a big, fat doobie. You've been returning that favor ever since, even at high school car-wash fundraisers. You got arrested for that.
A gift certificate to another restaurant
You got a gift certificate to a restaurant you don't like at an office party, and secretly wish you got that Crock-Pot® Jane in accounting scored. Fu**in' Jane.