Crisis mapping has had a major impact in the last 18 months, helping to collate information and coordinate activities during the Haitian earthquake in early 2010 and the Japanese tsunami that struck earlier this year.

But crisis mapping tools are increasingly springing up in politically fraught situations, too; most notably, they have been used to provide humanitarian relief during the protests that have swept through the Middle East in recent months. Since some authorities may want to undermine these efforts, or even attack those involved, it's becoming vital to protect these systems from interference, says George Chamales, a hacker and activist who has served as technical lead for crisis map deployments in Libya, Pakistan, and Sudan.

Crisis mapping tools—which combine communications technologies with a Web-based platform for analysis—can be used to organize information contributed by participants using mobile phones and other devices, and to display important updates on a live map.