I’m not a prankster, and don’t normally like them. But, sometimes...
Back when I was in graduate school, one of our lab techs related the story of a fishing trip he and several buddies had gone on. Planning to get up at about 4 am, they set up camp, had dinner, and everyone crawled into their sleeping bags for the night.
They waited until they were sure the intended victim had fallen asleep, then very quietly changed the time on all the clocks and watches and crawled back into their sleeping bags and pretended to be asleep. So when the alarms went off a little while later, they made a show of getting up, stretching and yawning, and saying things like, “I feel great! I’m ready to get out and fish!”
Meanwhile, the victim kept saying, “I didn’t sleep very well. I feel like I only got about an hour of sleep.”
So they went out on their boat and set up their fishing poles and waited. After a while, the victim looked at his watch and said, “Hey, guys? Shouldn’t it be getting light by now?”
“Naw,” they said.
A little while later: “Um, what happened to the sun?”
“Nothing. It hasn’t come up yet.”
As time went on without any signs of sunrise, the poor guy kept getting more and more scared.
They kept this up until about 7 am (by the victim’s watch).
Heh. We did that once to a guy.
He would come over and be a black hole of a party guy, as in, he couldn’t converse well at all, would get your attention and be unable to really complete a sentence as he got weird when the center of attention. Strange dude. Nice enough but strange.
One night he dropped by around 6 pm or so, and fell asleep on the couch about 7:30 ish. It was winter so it was dark. We set the clocks to 2:45 a.m. and posed like we were sleeping. One guy “woke up” and shook weird guy awake and told him he needed to go home. He left thinking it was the middle of the night.