A main advantage of the lightweight hardware that can be used to make a community intranet is its low power consumption. A good way to take advantage of this is to consider such a network in situations when a central power supply is unavailable. The same conditions that might make the Internet unavailable can cause normal power service to be unavailable.
A temporary solution to a lack of central power is to use a battery power source to temporarily power your network. Battery packs that direct power to a USB port are commercially available. As the Raspberry Pi and many routers rely on a USB connection for power this type of battery can be ideal. A fairly high capacity 9000mAh battery can be obtained for around 40$.