Community poster boards serve an important community building function. Posted fliers advertise services, events and people’s interests, and invite community members to communicate, participate, interact and transact. In this paper we describe the design, development and deployment of the Plasma Poster Network, a network of large screen, digital community poster boards, the Plasma Posters. An initial deployment of Plasma Posters is within our own organization, a software research community made up of technologists and designers. We present our motivation and two fieldwork studies of online and offline information sharing before describing the Plasma Posters and the underlying information storage and distribution infrastructure. Finally, we summarize findings from qualitative and quantitative evaluations of Plasma Poster usage and conclude by elaborating on socio-technical challenges that have been faced in the design and deployment of the Plasma Poster Network.