You have left out the Sadists. These are real people with a real problem, and they like forums like this because it is so easy for them to hide behind a screen and taunt holders as stocks fall, i.e. the jollies come easy.
Encarta definition of Sadism:
Sexual disorder, in which erotic excitement or gratification is derived from inflicting physical or mental pain on others.
The disorder occurs rarely alone; instead, it is usually combined with masochism, in which sexual pleasure is derived from pain that is either self-inflicted or inflicted by another person.
The combination is called sadomasochism. Sadism often involves binding, spanking, whipping, and, in extreme cases, mutilation and murder.
Among the many explanations of the causes of sadism is the theory that the sadist, most often a male with a low sense of self-worth since childhood, is trying to prove importance and superiority by punishing others.
The term sadism, which is derived from the name of the Marquis de Sade, is also applied in a nonsexual, general sense to anyone who delights in cruelty.
