MOB RULE is ochlocracy, not anarchy (mob rule is government by mob or a mass of people, or the intimidation of legitimate authorities -
http://en.wikipedia.org/wiki/Ochlocracy ). Ochlocracy is a lawless crowd - with no organization. In ancient greek 'ochlos' and 'demos' (the root words for oclocracy and democracy) are the possitive and negative words to describe a group of people. 'Demos' is all inclussive and it suggests that all citizens patricipate equaly. 'Ochlos' is diffenent in that it suggests a large group of people and not the whole of the communty. It gets its negative hue because it suggests the lack of organized decission making, therefore as a a system it has no facilities for any kind of judicial system and therefore it is unfair and it cannot serve the interests of the community at large.
A good example of ochlocracy was the Athens - December '08 riots. I lived it and even though we tried our best to set up councils and help organize and direct the people, we failed hard. That was because in a spontaneous revolt as it was there is no common ground. Everyone expresses their anger at each other and the state and serves their own selfish motives. Ochlocracy is bound to self destruct within a very short time frame as it completely lacks stability and justice.
Even if you confuse this with anarchy, i never supported such a system.