How has your boss (past or present) ruined your day?

I walked off the job at Frys Electronics when I found out my Manager hid my car keys from me. I asked him if he had seen them and he said no. An hour later I found them in his managers drawer. When I confronted him about it he laughed which pissed me off so much I quit on the spot. I was freaking out at the time because my shift just ended and I thought a customer took them.