Flame wars
The problem created by two or more users SHOUTING at each other online is entertainingly diagnosed by Clay Shirky. He makes some profound and pointed observations about how groups behave online, pointing out that computer software regularly ignores that people make most use of computers as part of social networks.
Shirky argues that open communities represent the “Tragedy of the Commons” where the group’s resources are owned in common, but each has an incentive to overuse those resources. He suggests that blogs work because they represent “enclosure”: an individual’s space can be coralled and protected without stopping being part of the commons.