I'm still trying to figure out what commonalities left-Libertarianism and Libertarian Socialism (etc) share with mainstream Libertarianism to justify the claim that they're "variations intimately related to" mainstream Libertarianism. They differ with regard to private property rights, the application of the Harm Principle, the desirability of State-enforced Positive Liberties, the need for a minimalist State and the importance of Negative Liberty. So, er ... what are these "intimately related" commonalities" that BigK HeX speaks of?