"My understanding is that the working principle of nabuur.com is to assist third-world village communities via the internet. I am interested to know if this has worked at all; and whether nabuur.com or any other website has a track record of success."

I would say the UN's Online Volunteering service has had success with helping people in the developing world by involving online volunteers. There are testimonials on the site from organizations based in the developing world, as well as orgs focused on such but based elsewhere.

I got to know nabuur.com through the OV service, FYI.