I'm not totally sure it is appropriate, and anyone with a low tolerance to immaturity would hate me for life. (And my friend, lol)
I have a British neighbor, he is a real ***hole, and we did the meanest thing to him, and I just got to watch him realize what happened.
(Fill in the blanks, I wore gloves)
At night, my friend had to use the bathroom. He used the bathroom, and I used my Gloves to place something inside his Grill. He didn't know until today, two days later. It smells TERRIBLE in his front yard. I just got to watch (through my window) him opening his grill, poking/getting disgusted over it, and then lighting it on fire only to realize what "it" truly is and dying from the burning smell.
I know it is wrong, I'm 18 so it's even worse, but I can't stop laughing. That is the single most hilarious moment in my life.
It's disgusting/wrong though, so sorry if people here take it the wrong way.