http://news.bbc.co.uk/1/hi/entertainment/4949488.stm A group of my old workmates used to do something similar by sending emails containing a full body of legitimate text to my colleagues, but also contained whited out suggestions as to how they could better themselves. This worked fine until the office baby-eater, who had fuller facial hair than I, received the email in rich-text format rather than HTML which, having converted all the text back into black, blatantly stated the time and place of an appointment we'd booked for her to have a a hot shave and further suggested that she have he saggy floor-cleaner of an arse stuffed and mounted. Some called it bullying. I called it the beginning of the path to self improvement. Needless to say that my emails were carefully montored after that, but it didn't stop me teaching the trick to anyone who would listen.