If pure Anarchy or Communism is to work, the premise "to each according to his needs, from each according to his ability" has got to be a realistic premise.
Under each of these non systems, government will ultimately become unnecessary. Everyone will be equal. There will be no bosses and there will be no classes. Each person will share possessions as well as the responsibility for getting things done, even the most mundane and menial tasks.
The last thing that Libertarians would have you believe is that they're anything like Anarchists or Communists. Libertarianism, as far as Libertarians are concerned, is a legitimate, responsible form of governance and the other two forms can only lead to chaos and probably totalitarian dictatorship.
In chapter 5 of his publication entitled THE STATE AND REVOLUTION, Vladimir Lenin writes, "From the moment all members of society, or at least the vast majority, have learned to administer the state themselves, have taken this work into their own hands, have organized control over the insignificant capitalist minority, over the gentry who wish to preserve their capitalist habits and over the workers who have been thoroughly corrupted by capitalism--from this moment the need for government of any kind begins to disappear altogether."