Libertarian Marxism?
Apart from Daniel Guerin - who identifies as Libertarian Marxist? Karl Korsch?
I don't know if Korsch identified as such. Guerin is the only one I know who explicitly used that label. But Korsch could certainly qualify as an influence on some of us who claim the label now.
Chomsky has called himself a libertarian socialist numerous times, if that relates at all
Most people say "libertarian socialist," or "anarcho-communist," instead. Depending on how diplomatic they want to be.
I find the term useful for its throwing most people's misinformed conception of socialism off. However, isn't it kind of a redundancy that lends credence to the idea of "authoritarian socialism" as being somehow socialist?
Chomsky has called himself a libertarian socialist numerous times, if that relates at all Chomsky has made it pretty explicit that he's not very familiar with Marx at all, though.