Social Networking and Nonprofits

I recently read a post about social networking and nonprofits on Betsy's Blog. I started thinking about how nonprofits can make use of social networking sites.

As a member of a bunch of social/business networking sites, I know nonprofits can make use of these sites.

Nonprofits can find future volunteers and employees by searching through profiles of members of these sites. Some of these sites allow you to create groups, many of them have a category for nonprofit groups. If a nonprofit creates a group, members can join these groups, and the nonprofit can see what members are interested.

I am interested in hearing about how nonprofits are using social networking sites.