sector. Engineers, scientists and software developers create open-source software projects. The Linux kernel and the GNU operating system are prototypical examples for the gift economy's prominence in the technology sector and its active role in instating the use of permissive free software and copyleft licenses, which allow free reuse of software and knowledge. Other examples include file-sharing, the commons and open access. Anarcho-communists advocate a gift economy as an ideal, with neither money, nor markets, nor central planning. This view traces back at least to Peter Kropotkin, who saw in the hunter-gatherer tribes he had visited the paradigm of "mutual aid". Anarchist anthropologist David Graeber in his 2011 book Debt: The First 5000 Years argues that with the advent of the great Axial Age civilizations the nexus between coinage and the calculability of economic values was concomitant with the disrupt of what Graeber calls "human economies" as found among the Iroquois, Celts, Inuit, Tiv, Nuer and the Malagasy people of Madagascar among other groups, which according to Graeber held a radically different conception of debt and social relations based on the radical incalculability of human life and the constant creation and recreation of social bonds through gifts, marriages and general sociability. The author postulates the growth of a "military-coinage-slave complex" around this time, through which mercenary armies looted cities and human beings were cut from their social context to work as slaves in Greece, Rome and elsewhere in the Eurasian continent. The extreme violence of the period marked by the rise of great empires in China, India and the Mediterranean was in this way connected with the advent of large-scale slavery and the use of coins to pay soldiers, together with the obligation enforced by the state for its subjects to pay its taxes in currency. This was also the same time that the great religions spread out and the general questions of philosophical enquiry emerged on world history—many of those directly related, as in Plato's Republic, with the nature of debt and its relation to ethics. Free shops Give-away shops, freeshops, or free stores are stores where all goods are free. They are similar to charity shops, with mostly second-hand items—only everything is available at no cost. Whether it is a book, a piece of furniture, a garment or a household item, it is all freely given away, although some operate a one-in, one-out type policy (swap shops). The