I'm a member of the online Progressive Exchange community, and thought some of my more tech-oriented nonprofit-type readers might like it.
It is a
way to share information among people doing online organizing, advocacy, marketing and fundraising on behalf of the public interest. The goal of the Progressive Exchange is to aid the online efforts of progressive causes, campaigns, and organizations.
I participate through a mailing list, which has considerable traffic, so be warned. It reminds me of older Unitarian Universalist function-oriented lists, but a bit more practical and concerning newer technology and practices.
It also has a New York, D.C. and Bay Area jobs list exchange in case you're looking for an employee, employeer or contract work.