After losing my contractor job with a Fortune 500 company, I learned of an "annoying coworker" feature on the internet that re-routes email messages from the original sender. I used it to compliment some of the people who supported me during my years there, and to needle those who undermined my efforts. My main antagonist eventually blocked those sorts of messages. She must have irked a number of people who learned of the website.
Once, at the same contractor job, I expressed mock concern that eating a poppy seed bagel might make me test positive for drugs. Within 24 hours, I was "randomly selected" to provide urine at a clinic nearby. My test was negative. The co-worker's--not so much--and the contracting agency reassigned him. I got a one-hour paid break from my daily routine though.