Years ago, back in our white box days, we were going through one of many system upgrades. Our backups took about six hours at the time. We had shut the machine down and started the backup process.
Our customer engineer came in about five hours into the backup. Trying to make good use of the time, he was checking on some cables and card locations. He always carried a "Mini-Mag" flashlight -- aluminum, but fairly hefty, none-the-less. Apparently the pocket protector was extra slippery that day; as he bent over to check another location, the light slipped out of his pocket and scored a direct hit on the emergency breaker.
It got VERY quiet -- partly from the sudden lack of machine noise and partly from the silence of the customer engineer! So, not only did we get to start the backup over from scratch, we got to go through a long recovery from the abnormal shutdown. Needless to say, we were late getting home for supper that day.Where do you want to go next?