In my ten years of flying, the experience that stands out to me the most isn't nearly as over the top as some on this thread. I was working on at a client call center in Panama City, Florida and our puddle jumper from MEM to PFN had been delayed about two hours. They had handed out lunch vouchers at the gate and the youngish passenger next to me decided to spend all of his on beer. After boarding, the flight attendant (who was rather young and cute) came by to do a seat belt check. My seat mate decided to cinch his as tight as he could and then proceeded to ask the poor flight attending if she would like to reach down and check how tight his was.

She looked at me, I looked at her, we both looked at him and she was absolutely speechless. She proceeded down the aisle with a shocked look on her face. When he subsequently asked for some alcohol once we were in the air, she was amazingly all out at our row. LOL.