AGI makes Satellite Tool Kit, an astrodynamics application for designing, visualizing and analyzing air and space flight. It does a lot of heavy lifting for government agencies, the military, and civilian aircraft manufacturers.
One use is the planning of flying unmanned flying drone (UAV) missions and the analysis of gathered data. Not everyone has an STK system installed, however, so now there is a utility that exports that data (and stuff like it) to KML. It’s shown in action in this YouTube video:
Watch it even if just for the eye-candy of seeing how STK’s virtual globe works. Can’t wait for this kind of augmented reality prowess to show up in Google Earth:-) Okay, maybe we’ll have to wait a couple of years.