I was working for an HVAC contractor and we did a job at a prison. We would work at night while all the residents were locked up and sleeping. We had a corrections officer escorting us the whole time. The hallways were all on the exterior of the building and lined with large windows. That allowed the guards in the towers outside to watch people moving within the building.
One night, in the wee hours of the morning, we're walking down the hallway when a red laser dot appears on the wall next to us. All of us contractors freeze instantly. We don't know what is happening and we DO NOT want to get shot. Our escort gets on his radio and tells the guys in the tower to stop fucking with us. The little red dot disappears and we go on with our night.
We were briefly afraid for our lives because some bored asshole prison guard couldn't resist flagging us with the muzzle of his rifle and teasing us with the laser sight.