On ye olde hpux this would work, especially when you did rm-fr /$var and $var was unset and nobody unit tested their shell back then. That db server ran for 2 days though with open file handles before it finally died.
Scene : 1998, Fort Bragg 18th Support Something-or-other, IT department
Date: 11th day of the month sometime before summer. Let's assume May.
Young Specialist looks at wall clock. Looks at time on the system. "I can fix that!"
Should I man date first? Fuck that, let's just do it!
Proceeds to set the time in the HP Unix minicomputer that handled all supply orders for the non Special Operations side of Fort Bragg.
Oops, set date to November 5th but with the correct time. No problem, we'll just run that date command again and flip the 5 and the 11 around. All fixed! Back to May 11th.
Comes into work the next day wondering why everyone is running around like crazy. All the processes have kicked off and are waiting for November to run again.
Ut-oh. Comes clean to NCOIC.
Aftermath: root was taken from all junior enlisted (good move) and only Staff Sergeants and above had it l. Oh, also the outside IT professional/Army civilian I assume.
Young Specialist gets written counseling (which was bullshit BTW- I made an honest mistake) and not UCMJ supposedly because I was going off to Kuwait for PCS (Permanent Change of Station) soon. Not allowed back on system.
Disclaimer: might have happened in June but either way I'm pretty sure I set the date to November and I know I got the date command order wrong at least once.