An article just published in the April, 2008, ArcWatch describes the use of ArcGIS Explorer during the search for a man lost in California's San Bernardino Mountains. Here's an excerpt from the article that describes using ArcGIS Explorer:

The 2008 search used a server that accessed a satellite broadband connection to retrieve ArcGIS Explorer 3D visualization enhancements. It was easy to overlay the polyline shapefiles created from the GPS track logs and display them in ArcGIS Explorer to create a 3D map. Aerial imagery or topographic map data was displayed as a background and draped over digital elevation models. Roads and administrative boundaries could be added for reference. This gave a true representation of the terrain difficulty, which was much easier for field teams to understand than a two-dimensional topographic map with contour lines. SBSO personnel were especially impressed that all this information is available for the entire country and can be accessed through the freely downloadable ArcGIS Explorer application.

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