Richard Horne has a freeware program 3DEM which is the coolest DEM maniuplation program anywhere. The program can make stunning 3D rotation movies, 3D VRML worlds and it spectacularly visualizes Digital Elevation Model data. It is the source of the visualizations here.
Visit the page.
Dear Dr. Horne:
I am a faithful user of Your wonderful software (3Dem84). Unfortunately, after having changed my OS (W98) to XP I am encountering annoying problems. I hope Your latest release will be of help for me.
Thanks
claudio scala