For managing a global nonprofit, Huddle has been great. They offer a fantastic upgrade (free) if you are 501c3 incorporated. That said, I have found their collaboration abilities to at par with what I know at BaseCamp and certainly better than say a Google groups. Huddle allows you to create multiple workspaces, manage teams and user access rights, set up appointments, assign tasks with owners and deadlines, it integrates with Zoho products for easy online editing of documents, Huddle has a wiki feature and of course a eRoom where you can upload docs. For managing multiple teams all virtual across the globe it has been great.