A long article at an Intel-produced online magazine explains how Intel leapt into action to bring computers and networks to the Katrina-affected areas: Nigel Ballard and Nancy Cox were two key figures, but they were given enormous leeway to take action. Thousands of Intel employees volunteered their efforts; Intel and their employees donated $7 million to the Red Cross, as well.
The company bought, borrowed, and reassigned thousands of laptops to get configured to Red Cross specifications to be used to register evacuees and connect folks. They also put together a huge number of fit-and-forget wireless packages that comprised mesh access points and Canadian-licensed WiMax equipment--the FCC granted a waiver for the use of frequencies currently unavailable here. Intel posted a map showing where they linked up transceivers for backhaul.
It's a good read, as it shows how people with their hearts in the right place can be aided by internal and governmental bureaucracy: key people can sometimes make quick decisions and then projects leap into being with little friction once the way has been paved.
Intel's efforts are just a part of the overall work that was done by volunteers and companies to reconnect people by voice and by the Internet during the aftermath of Katrina and so many other disasters since.