I'd love to know whether a BRIXMIS tale I was once told actually happened...
Some boffin wanted to know how thick the armour was on some new Sovietski tankski. So they gave a chap a boffin-jobber device and told him to find one of said tanks, hold the device against the tank's turret, press the tit and it would take a reading.
They didn't quite tell him everything though.
Chap finally found out where one of these tanks was parked, crept out in the dead of night with the boffin's toy, pressed it against the tank and pressed the tit as briefed.
A loud 'BOOOOOIIIIINNNNG' came from the device, which was obviously some sonar system. Chum legged it sharpish and about half-a-heartbeat later the turret hatch flew open and a dazed tank mate peered out in terror holding his head in his hands wondering what the hell had just woken him up..... It seems their crews sleep with their horses and/or tanks!
No doubt the touring team nearly wet themselves with laughter once safely back inside their Opel Senator or whatever...