Automated Retroactive Minimal Moderation
(ARMM) A Usenet robot created by Dick Depew of Munroe Falls, Ohio. ARMM was intended to automatically cancel posts from anonymous-posting sites. Unfortunately, the robot's recogniser for anonymous postings triggered on its own automatically-generated control messages! Transformed by this stroke of programming ineptitude into a monster of Frankensteinian proportions, it broke loose on the night of 1993-03-31 and proceeded to spam news:news.admin.policy with a recursive explosion of over 200 messages.
Reactions varied from amusement to outrage. The pathological messages crashed at least one mail system, and upset people paying line charges for their Usenet feeds. One poster described the ARMM debacle as "instant Usenet history" (also establishing the term despew), and it has since been widely cited as a cautionary example of the havoc the combination of good intentions and incompetence can wreak on a network.