Abstract:With the increasing economic accessibility of 3D printers, the lessons learned and the logics cultivated on digital Web 2.0 now seem applicable to the world of material things. Released in early 2012 by the artist groups F.A.T. and Sy-lab, the Free Universal Construction Kit is a set of 3D drawings that enable everyone with access to a 3D printer to make connectors between intellectual property restricted toys like LEGO, Tinkertoys, and Fischertechnik. However, when describing this project as "reverse engineering as a civic activity", it becomes obvious that the Kit's greater agenda is not just to enable cross-over playing, but rather, to problematize and perhaps ultimately open up closed formats through critical appropriation. But how does that, for instance, conform with the fact that the connectors are parasitically attached to these toys, whose logic it is simultaneously defying? And which (implicit) notions of creativity and play are at stake in this project, and to what extent do they fit the more general philosophical underpinnings of this project?Keywords: 3D printing, Intellectual Property Rights, Political Economy, Art, Critical Design, Appropriation, Creativity, Play Acknowledgements: This research has been supported by Aarhus University's interdisciplinary research centre for Participatory Information Technology, PIT, and AU IDEAS Pilot Center The Democratic Public Sphere. Thanks to the anonymous peer reviewers for valuable feedback and insightful comments."The crux of prefigurative politics imposed substantial tasks, the central one being to create and sustain within the live practice of the movement, relationships and political forms that 'prefigured' and embodied the desired society" (Breines 1980, 421)