what is the most mean spirited prank you ever pulled?

the guy I was going out with suddenly changed his mind and cancelled our flight to boracay I was so furious I called the airlines and told them that my wallet was stolen inside is my plane ticket! Next thing I knew the employee of that airline was calling me to say that they found my stolen ticket and that someone was pretending to be me! of course I denied knowing my ex!

My sister and I have another sister that is between us and we had to share a bed so we tried to give her a black eye. That was when we were kids. She always slept in the middle and we would give her the elbow. But we never really suceeded though. I don't know if she remembers it or not. But she was always the favorite. We were just trying to get even for all the attention that she got and that we didn't.

I used to be a police officer - and I was fairly strict. The day I became one, someone I hung around started calling me a "pig" and did everything he could to make me the classic "man." I resented this, since I had helped him out of jams several times. I also had turned a blind eye to his drug habit since he only did it in his house and did not drive.

After about a year of his mouth, I finally was seriously annoyed. I approached one of his professors at college and told her that he was under investigation for drug trafficking due to the amount of it he was using - he was suspected of selling (to be honest, he used a lot from what I had heard.) She called him in and explained that I could be compromising my job by telling her this, and told him he needed to clean up, or he could be sent to jail and lose all of his scholarships, not to mention destroy his life.

He started talking about how he knew who ratted him out - how he was going to clean up now, and stop smoking and drinking and get serious about his classes again. For a few months he jumped every time he heard a siren near by or he saw a police cruiser.

There was only one small problem, I had lied. There was no suspicion on him at all.

i put powerdered milk on my sisters bed and when she was sleeping it soaked into her skin. she smelled like rotten milk for days!!

so.. what did the person you pranked do to deserve that???