"In 1944, the Office of Strategic Services (predecessor to today's CIA) published a manual for civilians in occupied Europe with techniques for how they could support Allied resistance efforts in everyday life. The section on how to sabotage business meetings seems to have really caught on far beyond its original purpose"
via BoingBoing
https://boingboing.net/2024/02/12/how-to-disrupt-meetings-the-cia-way.html