Bringing post-Operaismo into network culture, this text tries to introduce the notion of surplus in a contemporary media debate dominated by a simple symmetry between immaterial and material domain, between digital economy and bioeconomy. Therefore a new asymmetry is first shaped through Serres' conceptual figure of the parasite and Bataille's concepts of excess and biochemical energy. Second, the crisis of the copyright system and the contradictions of the so-called Free Culture movement are taken as a starting point to design the notion of "autonomous commons" against the "creative commons". Third, a new political arena is outlined around Rullani's cognitive capitalism and the new theory of rent developed by Negri and Vercellone. Finally, the sabotage is shown as the specular gesture of the multitudes to defend the commons against the parasitic dimension of rent. (Contains 15 notes.)