Oh my gosh, that's totally something I would do!
I worked at a bank for quite a long time in a department that saw it's share of (I'm sorry to say) really idiotic people who had no right being hired for that position. (The Officer of that department was a real pushover for charity cases. It was the accounting department of a bank for crypes sake, once they hired a girl who had to ask how to turn on the computer the first day. ). My friend and I, who had to put up with these people, fix their mistakes and all around have to do twice as much work because of them, would work out our frustration by emailing eachother cryptic snotty messages about these people. One girl... who we referred to as "Chow Chow the Wonder Mutt" (ok, we were mean, but this was supposed to be private and she was sooooo DUMB) had made so many stupid mistakes one day and my friend and I were messaging back and forth. Next thing I know, my friend goes dashing to this girls computer (she wasn't at her desk at the moment thank goodness) and does some clicking. Come to find out she accidently emailed her a remark meant for me. Needless to say the snotty emailing stopped for awhile... but just for awhile.... ha ha!
No- really, I am a nice person! I just have strange ways of working out my frustrations!