announced last week that it had successfully deployed 5 wireless mesh networks in 5 different towns in Afghanistan, connecting local schools and libraries to the internet and each-other.
Freifunk uses Wi-Fi, the ubiquitous coffee-shop and home wireless solution, to create large-scale "mesh" networks that share wireless spectrum amongst each-other and can connect to the larger internet. A mesh network (technically, ad hoc mobile network) is newer form of wireless network that has the potential to be transformational as a grassroots, non-centrally-controllable communication platform for the global citizens movement.
A mesh is not formed by any central wireless tower (which could be easily shut down by authorities in repressive regimes) but instead arises naturally from many people directly connected to their local neighbors. Messages, video, pictures and the internet in general can be accessed by anyone in the mesh, just by jumping from one person directly to the next, in a chain, until you reach the person or website you want.
Mesh nets are resistant to being attacked, since they can just route the messages along a different chain if a particular node is knocked out or shut down. The messages still get out. For this reason, mesh networks are known as "self-healing", because they route around obstacles and attacks.
Wikipedia- Mesh Networking
Wikipedia- Peer-to-Peer (P2P) Network