While obvious devices to display a wiki city map include cell phones, PDAs, and smartphones, Kloeckl also wants more utilitarian structures, such as bus stops, to offer access to the maps.

"Everyone is familiar with a bus stop," he said. "So it's using the data with objects people are familiar with."

User interface issues also require additional thought, Kloeckl said. While users need to access the information with ease, uploading that data to the wiki also requires a simple method, Kloeckl said. He noted that the upload system must require little time and effort since some of the content will come from people who are moving around a city.

Finally, the data layers need to be arranged in such a way that a search produces pertinent results. Solving this problem involves further developments in the Semantic Web, an evolving component of the Web being developed by the Worldwide Web Consortium. The Semantic Web aims to take data and apply standards that allow computers to play a greater role in locating, finding, and presenting information. This will permit computers to understand the standards and produce more contextual search results.

"We need information that is time and place relevant so it can be queried on a semantic structure," Kloeckl said. "We need a way to structure data so that it can be cross-queried."

Pedestrians may eventually turn to interactive maps to avoid the masses or catch a bus, at the same time that their movements become part of the map's display.