I love to play jokes on people at work. I have been known to "email bomb" people, which is jumping on a co-workers computer and sending emails to other people in the building. I have also played jokes with packzi's, paged fake intercom announcements, the list goes on and on.
However, I have never tried to poison anyone I work with (except Chris Monroe). A Virginia woman is in big trouble after she was recently caught poisoning her co-workers' drinks with Visine.