"Transition Towns (http://www.transitionnetwork.org, http://www.transitionus.org, http://www.transitiontowns.org.nz, etc.) is one of the fastest growing social movements in the world today. It's a bottom up movement made up of initiatives around the world collaborating locally and widely on community based answers to peak oil and climate change around the world, supported by Transition Network and affiliated organisations.
Drupal at the centre of a lot of the web developments. This group exists to bring together Drupal builders, site admins and developers with an interest in Transition, for knowledge sharing, and joint development activities."