Not the cleaner for once.
Way way back at the Uni we had a cleaner unplugging stuff on a regular basis.
So one day when a server was down i made my way over to the dingy "server room" to plug it back in.
Opened the door and saw a rack with halfmelted servers slammed the door and called the fire department.
Turned out a holding tank of sulfuric acid on the floor above had sprung a leak.