The organizations I work with, not just in the developing world but in the USA as well, do not have the latest and greatest technologies, and they won't be able to afford them anytime soon. So many, if not most, of the
software listed here aren't options for them.
A tool that has proven invaluable to me in working with organizations across distances has been
YahooGroups -- because it an work on just about any web browser, including older browsers, because it's free, because it offers so many features, and because it's so easy to use. From long-term collaborations to short-term online events, it's made a lot of sharing possible in my work that never would have happened otherwise.
I've been experimenting with
ivisit.com (my id: jcravens.4947), as a Skype alternative, since its much more compatible with a wider range of computers and platforms. But I'm still not impressed enough to give up my phone. Plus, most nonprofits I work with lack the tech knowledge to know how to install and use this software themselves.