Libertarians and Marx

I've always looked at Libertarians with a slightly jaundiced eye. Once one gets past the populist "Reefer and machine guns for everyone!" aspect of their philosophy, and disturbing materialism becomes apparent. The fact that this materialism is in the service of the sovereign individual as opposed to the dictatorship of the proletariat in Marxist materialism, is no defense as far as I'm concerned. Materialism is evil regardless of who or what is being served by it. I always wondered if there was a connection between Libertarianism and Marxism, aside from the surface-level connection that both philosophies seem to produce ratchet-jaw ideologues that make poor company and tend to spoil the conversation at genteel dinner parties. Even the much-vaunted individualism of the Libertarian counts for very little when this sovereign individual is reduced to an abstraction, or to quote a certain Libertarian, "Consumers are necessarily free agents who exercise choice among competing alternatives."
Thus it was much to my delight that I found an article which makes the connection between the two:
Why Karl Marx supported Libertarianism