OAN -Open Architecture Network

Open Architecture Network is humanitarian open source software that aims to connect architects around the globe to struggling communities. OAN is a free Web-based open source community dedicated to improving living conditions through innovative and sustainable design. The downloadable software contains a database of architectural projects and a free architectural design tool that can be used my nearly anyone, not just professionals. Cameron Sinclair, the designer of the software, imagines that the site will not only help create, support and implement ideas, but also be a place that fosters sustainable, replicable, adaptable and scalable design solutions.

You can find out more at their homepage.