A group raising money to buy unused telecommunications satellites and re-purpose them to provide access to undeserved geographies.
A Community Wireless group operating out of Germany, whose standards and routing protocols have gained worldwide popularity.
A group producing low-cost mesh hardware.
Mesh networking on Android phones
Some folks in Australia have come up with a way to do mesh networking over Android phones, if they are close enough together. Their system provides a way to use VoIP over the mesh network, although the voice quality is poor.
According to its creator, a professor at New York University,
PirateBox is a self-contained mobile collaboration and file sharing device. Simply turn it on to transform any space into a free and open file sharing network.
It consists of a Debian GNU/Linux computer with a Web server attached to a wireless router. It has no Internet connection, so you can't use it for downloads from external sources -- it's only for sharing among the people who can access it directly. No passwords, no logins, no authentication. The creator claims that you can build it for under $100.