Pro/ENGINEER
Pro/ENGINEER is a popular 3D CAD program created by PTC.Commonly called "Pro E", or just "Pro". It seems pretty popular, definitely powerful enough to do serious engineering work, but has a fairly un-intuitive interface (which doesn't follow common Gui conventions that modern computer users have learned to expect). Since the 2002 release of Pro/Engineer, that is called "wildfire", the software made great progress with the GUI.
Pro/Engineer is one of a few CAD-software products that is available for various Unix-dialects, Windows and Linux. All data is exchangeable between these platforms without conversation.
