A little offtopic as this doesn't directly pertain to Wikimedia, but thought this was really fascinating - an organization has established a grassroots, community run mobile network in Mexico (and as I understand it are trying to do something similar in Nigeria), using free/libre/open source software:
http://www.telecompaper.com/news/mexican-rural-community-creates-own-mobile-...
And if you read Spanish, an article from La Jornada: http://www.jornada.unam.mx/ultimas/2013/08/17/94147812-telefonia-comunitaria...