Re: Closest I've had to that ....
We had a good one in the 90s - the mail order company I was workig for were doing rather well and had decided to extend their warehouse a bit to cope with all this stock they're happily selling (that's another story).
At the time the ssytem ran on an HP Unix Fridge whose 2 19" racks pretty much filled our little server room. We were located in anothe office across the hall with the boss in the next office to ours. On the day in question one of our number was having his appraisal (review) in the bosses office.
The builders were digging trenches with a JCB. Now they did everything theuy were suposed to do, the plans for the building showed that the electric cable went along this end of the building and the water went out the other end - allegedly. Cue JCB digging a trench about 1/3 the way between the 2 corners, now what could possibly happen?
The first we saw was the screens on our PCs went a bit squiffy (this was the era of CRTs - the picture something like a Picasso painting for a few seconds). 'Hmmm, wonder what's going on' I say and wander into the server room - 2 feet inside the door and BOOMM!!
Next, cue the boss & the guy getting his appraisal dashing in expecting to find me with a charred screwdriver or the like. Turns out the UPS protection circuits on the Unix box did their job admirably and protected the main system by blowing themselves to bits. Turns out those electric and water conduits weren't where the plans said they were but instead were in the exact position the JCB was digging, and he caught both of then with the bucket at the same time.
We managed to get the UPS fixed under the 24/7/4 service contract (and that included shipping a new one from 50 miles away, no mention was ever made about the JCB drivers trousers though.
Ah, happy days.......