MIT's Climate Colab
The goal of the Climate Collaboratorium project is to harness the collective intelligence of thousands of people around the world to address one of the most important problems confronting humanity today: global climate change. Inspired by systems like Wikipedia and Linux, the project is developing a global, on-line forum in which people can create, analyze, and ultimately select detailed plans for what we humans can do about global climate change.
Liferay is used by MIT's Climate Colab the sourcecode for which is here.
Latest ClimateColab software is now here. The new codebase is greatly simplified over the earlier version; it still relies on Liferay, but appears to drop the IBIS structured conversation platform in favor of forum format (discussion portlet rather than debate portlet)