The recent fires in western USA showed how technology can help the displaced urban dweller, provided that the authorities are moving with the times as well. In October 2007 over 250,000 residents in San Diego were displaced into shelters such as schools and football stadiums.
Many residents took their mobile phones and laptop computers with them when they evacuated. Some shelters set up dedicated computer rooms together with Wi-Fi systems connected to the internet. Evacuees could email relatives and friends, as well as keep up-to-date on the news about the fires. This reduced a lot of stress.
Because of the numbers of people brought together in small regions the mobile cell towers could not accommodate the number of users trying to make calls (you might know that Telstra installed a number of temporary transmitters around Sydney Olympic Park in 2000 for this reason - you can imagine 60,000 people calling friends after the 100m final). People were therefore encouraged to use SMS rather than voice calls, although those with VoIP phones such as Skype (recently now available from phone carrier 3) could use those over the Internet.
San Diego has "Reverse 911", which allows the authorities to automatically dial all phone numbers in specific areas with emergency information. This has been limited to land-lines to date, but it is conceivable that the same could occur to all mobile phone users in a given cell-tower range, subject to the capacity of that cell-tower. There might also be other issues with people getting multiple calls as they move into adjacent cells, but I'm sure someone can solve it.
Many people forgot or couldn't take their charging devices with them, or the mains power was out. With judicious use of the equipment many users were able to stay connected on and off for days, turning things completely off when not in use.
Some shelters used "mesh networks." These are Wi-Fi networks that don’t rely on a single transmitter and access point. Instead, each computer in the area becomes a little transmitter as well, meaning that if you had a line of 1000 people 10m apart you could have a network stretching out 100 km! Otherwise that 1,000 people would have to be clustered in a circle 100 m radius around the transmitter.
Of course, the relief workers benefited from this technology too, and their job was made easier because evacuees could be a little less anxious through access to information.
Sadly, many people went home to charred blocks of land. It's hard to imagine how many digital photos, financial records, letters and more disappeared. Some may have had backups, but they may have been destroyed as well unless they were kept off-site. You can do that using Internet services (there are dozens, and I use http://idrive.com for no particular reason) or just copy everything to an external USB hard disc once a week/month and leave it at work or at a relative's home. I like the convenience of Internet based services, as they just inspect my files each night and back up anything new or changed. I even get multiple versions so I can roll back to a previous version if necessary.
While considering what else may be of use in a disaster area, I thought about mobile broadband such as that offered by 3G phone providers or Unwired. You could be sitting in your car trying to evacuate and be able to see roadmaps or evacuation route advice. A GPS would be helpful too. An iPod would pass the time, but would otherwise be useless as it doesn't have a built-in radio, unlike, say, the Zune or many others.