In which things get Very Bright and then Very Dark.

Some years back, I was visiting the systems programming group at the state Department of Human Services. This was back when folks who herded mainframes for a living used IBM 3270 terminals, rather than PCs, and losing power just meant that you had to turn your terminal on again and log on to the system again, not that you had to reboot a PC and start this, that, and the other.

There was remodeling in progress in their area: a new doorway was to be cut out of the wall, and a frame and door installed there, following which the existing door and frame were to be removed and the opening closed up. The workmen started to cut the new doorway -- from the outside.

On the inside, my host and I saw, at the same time, that the saw blade projecting through the wall was headed downwards ...

towards a fourplex power outlet. An ACTIVE fourplex power outlet.

We both shouted "Turn off all terminals now Now NOW!!", just before the blade went into the box, sparks flew, and the lights went out.