NASA has released a number of free programs that may be of interest to educators, including one called World Wind. This is essential a virtual globe composed of satellite imagery that you can spin, tilt, zoom, and enhance with digital elevation data. Layers such as boundaries and place names can be turned on and off.

The program requires 2 GB of hard drive space and a high speed Internet connection. It is NOT a program to be run on an older computer. The program download is 128 MB and requires Microsoft.NET (another 28 MB and also free) and DirectX runtime (also free) to run.

This is an impressive free program though it is difficult to navigate and control what appears on screen. Though the surface can be enahnced using SRTM elevation data, in some areas this was non-existent. The program has much potential (a flyby creation tool would be helpful) and is of interest to geomatics professionals and educators.