The Aid Workers Network is a UK-based nonprofit created in 2002 by a group of aid workers. According to the FAQ page on the site, over 12,000 aid workers are registered members of the community.
The site includes a news aggregator that pulls from aid workers' and aid organizations' blogs, including a great looking blog called, humanitarian.info. One of humanitarian.info's posts pointed me to the UN's Office for the Coordination of Humanitarian Affair's Virtual Humanitarian Information Centre for Lebanon. OCHA also has Virtual Humanitarian Centres for Pakistan, Niger, Sri Lanka, Sumatra, Darfur and Liberia.
pingVision wrote up a short piece about their work on the Network that says that it is a "CivicSpace-powered site" that is "powered by Drupal's phpTemplate theme engine." They also designed the logo.