When someone forgets to log off their email or facebook on a computer and another person sends out an email to their address book pretending to be that person. (Normally pretending to come out of the closet or something gay.)
Practical joke that normally takes place in the workplace.
Dude I just read an email sent from Chase. It says "he loves cock" and that "he enjoys rubbing his balls on Morgan's mustache." Someone must have fag-mailed him.