Ah, the power of open. A team of people (mainly developers) has come together to develop a new communication method for times when existing infrastructure just doesn't work. They've come up with two systems:
The Serval Project consists of two systems.
The first is a temporary, self-organising, self-powered mobile network for disaster areas, formed with small phone towers dropped in by air.
The second is a permanent system for remote areas that requires no infrastructure and creates a mesh-based phone network between Wi-Fi enabled mobile phones, and eventually specially designed mobile phones that can operate on other unlicensed frequencies, called Batphone.