From 8by1.com:
8by1 is a wishlist for your world. 8by1 helps you evangelize your wishes for the world, and connects you with similar-minded people who also want these wishes to come true. The 8by1 community empowers even the casual people like you and me to make our world how we like it.
This is distributed philanthropy, using the internet to empower geographically dispersed individuals to provide others in need with small one-time gifts of financial assistance.
MatchingDonors.com main objective is to search the world to find potential live donors for people in need of organ transplants.
SchoolNet Africa is an independent non-government organization which promotes education through the use of Information and Communication Technologies (ICTs) in African schools.
TakingITGlobal.org is an online community that connects youth to find inspiration, access information, get involved, and take action in their local and global communities.
www.malecare.com Provides support services and an online community to gay men with prostate cancer.
Congresspedia is a collaborative project of the Center for Media and Democracy and the Sunlight Foundation and is designed to shine more light on the workings of the U.S. Congress. Congresspedia is part of SourceWatch, a collaboratively-written, wiki-based website documenting the people, organizations and issues shaping the public agenda.
SourceWatch is a collaborative project of the Center for Media and Democracy to produce a directory of the people, organizations and issues shaping the public agenda. SourceWatch's primary focus is on documenting public relations firms, think tanks, industry-funded organizations and industry-friendly experts that work to influence public opinion and public policy on behalf of corporations, governments and special interests.
The Wikimedia Foundation is a 501(c)(3) nonprofit organization with a vision to bring a free encyclopedia to every single person on the planet. This includes people who currently do not have electricity, computers, internet, or even clean drinking water. All proceeds from donations, as with all proceeds from all fundraisers, are fully dedicated to that charitable purpose.
Link to a NetSquared post about an amazing wiki called Blogsafer.org. Focusing on areas where persecution of bloggers has been the worst, BlogSafer.org contains guides on how bloggers can avoid state persecution around the world.