Christian writes: "Bibliograph  is an feature-rich open source on-line reference manager and collaborative bibliographic tool. It consists of a multi-user management application with a user-friendly graphical interface and extensible and configurable import and output plug-ins which accept or return bibliographic data in a variety of formatted styles or coded formats. Bibliograph is ideal for groups of researchers to build and maintain a bibliographic database, and to publish bibliographies in the internet. A demo  is availabe. You can download version 0.98.1 here ."