Reddit, what's your best/funniest personal example of petty revenge?

My first job decades ago was "editorial" for a small craft magazine (let's say the theme was quilting). Pay was $20K, but I accepted it as my foot-in-door. I liased with the advertisers (keeping the back cover advertisement the same as I was advised to by graphics team) and wrote everything in it; the craft instructions, the interviews with craft celebrities... even the editor's letter. The editor's letter was issued under a fake-sounding relevant female name (let's say "Ida Down"). So I continued writing it in the established style (sweet old grandma excited to craft quilts), always ending it with "happy quilting my dears, love Ida Down" and inserting the pink scrawly Ida Down signature my computer had saved as a JPEG file. Subscriptions grew. Sales flourished. One year passed. As I sat in my office typing, I look up to see a sour-faced hag snap at me, "I've come to express concern at the discolouration of my back page advertisement," whilst thrusting the last issue in my face. Was this the mystery back page advertiser? Geez that image was dark! I almost leave to get the graphic designer for her, but turn back apologetically to ask her name. "I'm Ida Down, the editor... get me a coffee too kid," she barks dismissively. I'm in shock! Ida is a REAL person? I'd thought she was just a myth perpetuated by us all to sell copy! I go straight to the director and point her out, whispering fearfully that some psychotic lunatic in my office claims she is Ida Down... He says "But, of course that's Ida, how do you not recognise her?! She's your BOSS, and in every day..." After much confusion, I discover that Ida was indeed real, had reserved an ad for her craft supply company on the back of the magazine for years without paying for it that nobody ever noticed (because hey, it's a frigging craft mag, not the top shelf glossies) AND she had been claiming $100Ks in annual salary for supposedly daily working on the magazine for years ...but stopped showing up several years before when they starting hiring her an editorial aid. Guess the badass realised we poor saps (several came before me and were called during the subsequent inquiry) were young/ naive/ desperate enough to be used. Needless to say, by merely inquiring about her, I got her fired... the previous "editorial" girls were amazed she was not just some pseudonym, and she was made to apologise and I believe to return some misappropriated funds to the company etc. Thinking about it now though... what a fucking badass crafty bitch, she was kind of cool.

/r/AskReddit Thread