It was the 1970s and the end of a busy nightshift in an ICL mainframe computer room of a Datasolve computer bureau (anyone remember those?). The line printers were kicking up a row. The tape decks chugging back and forth, the EDS60 disks spinning and clicking, card readers doing what they did.
In comes the caretaker and his vacuum. All of a sudden.
Total silence. Power fail?
All eyes focus on the caretaker, rapidly reversing towards the door still cleaning with his now dead vacuum.
He had hit the emergency stop button with his elbow.
The guy was a walking disaster: once scrapped a whole bin of punch tape that took hours to create because he thought it was rubbish.
Those were the days.