John Suler's The Psychology of Cyberspace
Everyone has a dark or "evil" side to his or her personality. The definition of "evil" varies from person to person, although usually it has something to do with malicious, aggressive fantasies and/or feelings of guilt. Note how many Halloween costumes fit this category. As a form of sublimation, evil costumes allow people to safely - and even creatively - express their dark side. While some members may wear an evil av as their facade for the evening (which may reflect their mood at the time), others may "flash" it as a momentary cue to others. Mess with wizards, for example, and they may flash their evil av as a warning that they're getting annoyed and may pin, gag, or kill you. On one occasion, I witnessed a male come on to an attractive female member wearing a real face prop. When her attempts to brush him off failed, she flashed a nefarious looking skull at him. He quickly backed off. Some people may use evil or aggressive avatars as a way (consciously or unconsciously) to alienate or "put off" other people. This might indicate their anxiety about intimacy and being vulnerable.