Social networking for architects & disaster relief workers

A lot of people think that social networks are for people with far too much time on their hands; for teenagers, for people who wear heavy metal t-shirts and haven't seen the sun since 1972, or for agoraphobics.

What I'm interested in however, is how we can use social networking and Web 2.0 tools to help us use knowledge and information in our everyday lives. Although I'm researching this from an NHS perspective, I've found some other interesting examples of social networking sites which are used by professionals to assist humanitarian relief.
I have a couple of friends who are architects and I think the Open Architecture Network is a fantastic example of a profession sharing knowledge across the world to help them aid people who are suffering due to disaster or poverty. Check it out, it's interesting even if architecture isn't your thing!

I also found an interesting article about how some relief organisations are using wikis to share knowledge quickly in emergency situations. This article's focus is however around how access to that knowledge is still far from ideal due to the construction of the Internet and the way that data is currently searched. It argues that Semantic web (a.k.a. Web 3.0) processes will help t0 label information in a way that makes it much more easily retrievable; something which is beneficial for all users of the Internet, but especially to those where quick access to information is vital. Very interesting.