the big red button
I worked at a place which had two main processing centres and a number of satellite mini-centres around the country. One of the mini-centres at the time actually shared the building of one of the main centres, albeit on another floor, but was being decommissioned. It finally reached the point where decommissioning was complete, and all the dayshift operations staff were standing in the main centres machine room talking about it with our manager 'Terrydactyl' (he was a bit old fashioned in management style). He took it upon himself to push the 'big red button' on the pillar next to him to officially power the satellite centre down. Everyone around him shuffled nervously in their shoes. The whole main processing centre went down immediately. Funniest thing to see his face when the lights came back on!