X-Plane is incredibly extensible. You can simulate new aircraft, make 3-D models, or even change the functionality of the program in drastic ways.
World Editor 2.6r1 is now available. This is the first release candidate, for which we encourage you to explore before we lock it down for release! Version 2.6 packs quite an extensive feature list. Features include :
New Shape Entities
Allowing users to define lines and polygons, and then export to .kml Read More
