Being given at the "perfect" time is its allure.

My ex-boss had a gift for doing that. We worked at a law firm and one of the partners came walking in with a midget. He introduced us to his brother. As soon as they walked away my ex-boss leaned over and whispered to me, "It must be his half brother". It was said 25 years ago but I still remember it (as one of the funniest things I've EVER heard).