ArcGIS Explorer: "ArcGIS Explorer is a geospatial information viewer that offers a free, fast, fun, and easy-to-use way to view geographic information in both 2D and 3D while performing queries and analysis on the underlying data. ArcGIS Explorer integrates the rich world of GIS datasets and server-based geoprocessing applications. It does this by accessing the full GIS capabilities of ArcGIS Server including geoprocessing and 3D services. ArcGIS Explorer can also use data layers and services from ArcIMS and ArcWeb Services. It supports Open Geospatial Consortium WMS and Google KML data, making it open and interoperable. With ArcGIS Explorer, you can - Explore data for the entire world in 2D and 3D seamlessly. - Fuse your local data with data and services from ArcGIS Server, ArcIMS, Open Geospatial Consortium WMS, and ESRI-hosted ArcWeb Services. - Perform GIS analysis using tasks (e.g., visibility, modeling, proximity search). - Answer geographic questions about the maps you generate and share the results with others. - Use maps and data from your own secure servers. "