I once worked at a company with 1,500 employees in one location. One Friday, about 11:45, a message over the Public Address system announced there was a fire, and people had to evacuate. People left the building and went off to long lunches, as it was clear it would take a while to sort things out. Fire announcements continued to be made on Fridays before lunch, two or three times a month. People enjoyed their three-hour lunches, and company officials went bonkers trying to stop the announcements. They never found out who was doing it, even though the ability to use the P.A. system was supposed to be password protected and highly secret. Suspicion certainly fell on the 100 or so hardware engineers and programmers, any of whom might have hacked into the P.A. system.
I'm taking a long weekend, may not blog again until Monday.