Sal sez, "Three years after Cory's novel Someone Comes to Town, Someone Leaves Town,' somebody actually made a router that does what the fictional mesh-network routers from the book could do.
The Fonera 2.0 made by FON, (the Spanish WiFi sharing people) is released today (barring the occasional retail glitch) for 45 euros. It comes complete with OLPC's mesh-networking system.
You can plug it into Ethernet or a 3G dongle. Share your bandwidth with any other router in range that implements OLPC's mesh-networking standard. The Open WRT software is designed to run on just about any hardware so you do not actually have to buy a Fonera to join the fun.
The software is based on Open WRT, which in turn is based on the Linksys WRTG54G firmware which the community forced Cisco to open-source (since it made use of Busybox + Linux Kernel).
As a result of this we now have a router far more featured than the most expensive access point you can get in the shops, costing a fraction of the price and based on entirely free firmware.
With a few of these we could all build community networks like the one from Cory's book."
Fonera 2.0
(Thanks, Salim!)