Drupal
How do you get civil society engaged in public online monitoring of your project? Even if you design a killer website for interaction among stakeholders, it will be of absolutely no value without visitors. And chances are that unless you're a seasoned search engine optimizer or have a very large budget at your disposal, nobody will ever find your website. This is where social networks enter the picture.
OpenAid is implemented in Drupal, the award-winning open source content management system. In true crowdsourcing spirit Drupal is being developed and maintained by more than a thousand people worldwide. Its modular architecture makes it very easy to implement and deploy new modules that extend the core functionality. OpenAid uses about 15 such 'contributed' modules.