Essentially, what I have in mind is a network of free wi-fi hotspots tied together by cheap unlicensed devices like those made by Ubiquiti, with enough redundancy such that it could tolerate the occasional link outage due to interference or device failure. The network could be tied into the greater Internet in myriad places such as universities or municipal networks, without ever touching the likes of Comcast or Verizon.
I have not thought this through; it is just an idea. Do any of y'all think it could be done?