An online TP system in the 1970s had two development teams. One day a bright youngster in the distant one got bored and decided to wind up the main centre. The main console suddenly printed "I am a ghost and I have changed your password". This was true and the systems team scrambled into debug mode to find the new master password (in the days before encryption was used).
Before they had succeeded - the message appeared again - and again - and again. Each time it changed to a new password. All was revealed when the guy rang through to see if they enjoyed his creative joke - and it then dawned on him that his code had a bug that made an unintended loop.
He was fired the next day.
Biting the hand that feeds IT
