Pranks in the workplace are often frowned upon, but when it comes to petty revenge, perhaps there's an exception. We all loved the high school pranks where the seniors would streak, saran wrap the school staircases, or fill the entire art room with cups of jell-o, but when you're an adult, things start to get a little spicier in the prank department. One man, a coffee lover with with a caffeine addiction and a hard-pressed nerve for revenge...