years ago, i had a co-worker who was a real jerk. The business owner decided to make him store manager. It was a really stupid choice because he was full of frustration & anger & he took it out on employees and customers. Unlike my co-workers, i didn't take it from him & that made him more angry. He'd leave me notes on what needed to be done before the end of the day & he'd talk to me like i was 8 years old. I told him, "ya know, you're not making me look stupid; you're making yourself look stupid...but then...you don't have to work very hard at it."
there was a clean erase black board in the lunchroom. To get back at me, he left a note on it that read: (mistakes included) "as the duke once said lifes sure hard but its a lot harder when your stupid." it was in blue ink. I took the red marker & corrected all his mistakes.
Then, i wrote under his note: "he was right."
when he went into the lunch room, i watched him staring at the black board, then he gave me a mean look for 2 minutes straight! It took me 20 minutes to stop laughing.