There are some insults that are so creative and well-timed that you have no choice but to put them in your pocket and keep them on-hand for the future.
In fact, some insults are so perfectly piercing that even if you're on the receiving end you can't help but respect the game.
“You look easy to draw.”
When my daughter was little (about 4), we spent the night at my parents and I was brushing her long hair after her bath. My dad told her she had such pretty hair, and asked if he could have a little to cover his bald spot. She didn’t even look up and said “I think you have enough on your back to cover that.”
"You have the communication skills of an alarm clock."