An interesting project launched a few months ago worthy of specific note. Airchat (open source code on Github here) provides a basic protocol for making a rathe anonymous mesh network with radio gear, or other means of transmission. It can convert analog audio to and from packets, so that a HAM radio rig or other type of radio can send encrypted signals into the air and the correct other nodes can pull down the signal. Its developers claim to have used it at some distance.
The catch, of course there is one, in the USA and UK it is forbidden to encrypt information on public frequencies under FCC rules. Like all class pirate radio movies the FCC vans could come for you if this gets too big.
Still on a global scale it has obvious humanitarian utility such as transmitting digital medical information over more than 100km on cheap gear without any existing phone or internet connection. It also can do low-bandwidth digital audio. Truly this could make a major positive difference & I hope that its use can be extended.
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Writeup: Airchat, The Wireless Mesh Network From Lulzlabs
Some funny comments at Anonymous' Airchat Aim: Communication Without Need For Phone Or Internet - Slashdot
The fun intro video Airchat on Vimeo
Airchat from #lulzlabs on Vimeo.
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Another writeup from h+: AirChat: Secure Wireless from Anonymous -
Sounds pretty nifty. Good luck with that!