I remembered reading about the OSSIM project in a LinuxPlanet article http://www.linuxplanet.com/linuxplanet/reports/4101/6/ about the company responsible remotesensing.org http://www.ossim.org It's a GIS application that is part of the remotesensing.org project and it uses MPI. I haven't used it, but I bet it would make a good demo. -Andrew