This article will introduce the Open Siddur Project, which aims to be the first of a new breed of Jewish communal resources that use social web technologies to allow the sharing and collaborative development of online Jewish liturgical resources. All content will be fully reusable and redistributable under liberal terms compatible with a “free culture” philosophy. The article first defines “free culture” resources, and explains why such a philosophy works to the advantage of their users. It then discusses the envisioned product, followed by a brief discussion of its current state of development. Finally, it contrasts the project with existing resources.