Startup Idea : team up tool for social enterprise or non profit

What about a site for people with various backgrounds and passions .e,g,(scientists, artists, web developers, conservationists, social workers) where they can get together/team up to brainstorm ideas for social/environmental good and turn them into action. Something like a decision-making tool ( collaborative). It would be thus something similar to this site but much more extensive ( e.g. There might be links to various organizations/information, there might be a place for story telling, etc.). There are many sites, but many already promote specific projects/ideas or just talk about them on their blogs. People ask questions but they get only short answers. This would be about collaboratively coming up with an idea for social enterprise or some other activity for social good and putting into action.