This essay investigates the rhetorical practices of socio-technical deliberation about free and open source (F/OS) software, providing support for the idea that a public sphere is a socio-technical ensemble that is discursive and fluid, yet tangible and organized because it is enacted by both humans and non-humans. In keeping with the empirical shift manifest in recent public sphere scholarship and Bruno Latour's idea that socio-technical deliberation is characterized by the inscription of non-humans, I describe the rhetorical manners in which volunteer citizens define and mobilize a mundane artifact--a web site--in a deliberation over the value of F/OS technologies for their government-funded project. Through inscription of the web site as a rhetorical resource and as the embodiment of their disposition toward computer technologies, the volunteers formed and expressed competing understandings of the role of F/OS technologies in sustaining a public sphere. I argue that these competing views are consequential, for they link technical artifacts and political agents in practice, by way of aspirations, obligations, and forms of authority. Furthermore, by claiming a form of agency for technologies in the public sphere, the proponents of F/OS technologies are inviting scholars of the public sphere to question the status assigned to technical artifacts in their investigations and theories of the public sphere. (Contains 1 figure, 1 table, and 65 notes.)