One of the mailing lists I was on suggested that the best way to provide network access to a neighborhood was to use a mesh architecture based upon the Meraki nodes. I seemed to have vaguely recalled seeing them before, so I went to peek. They look really interesting, and quite competitive pricewise ($99 for an outdoor node, $49 for an indoor one). I haven't used 'em, but they look really cool. If you have the need, check 'em out.