MIT spin-out Meraki Networks has made a huge impact on the wireless community networking space through their bargain-basement open source-based wireless mesh network products. An out-growth of MIT’s Roofnet project, which provided wireless access to over 1.5 square miles of Cambridge in 2004 and 2005, Meraki’s network covering 1.5 square miles in San Francisco’s Mission District is now San Francisco’s best chance at getting a city-wide network in the face of recent political challenges.

The network will cost only about $15,000 and relies on the grassroots volunteerism that have made both MIT Roofnet and Meraki such successes. Over 300 people have already volunteered to host nodes as part of the “Free the Net” campaign, many of whom are also volunteering their DSL connections or allowing Meraki to install DSL connections. Some CLECs, such as Speakeasy and Sonic.net, have SLAs that allow subscribers to provide free or resold Internet access, which enables Meraki to use advertising to support the network’s operating costs.

Check out their progress at sf.meraki.net. A recent one-month pilot using three Meraki nodes in Cambridge’s Harvard Square netted over 700 unique users, and the San Francisco network already has over 2,000 unique users despite being only about half completed. The Free the Net project questions the current paradigm of big telco buildouts using enterprise-grade equipment promoted by industry giants such as Earthlink and AT&T. Given Earthlink’s recently announced first quarter financial losses, questioning the current models for city-wide wireless Internet seems like a good idea, although the jury’s still out on whether this new model will succeed.