I have resurrected the original xearth page at xearth.org. Currently this is the original (non-Windows) xearth page but I intend to pick up development of xearth going forward. I have created a Github repository containing all the past versions of xearth that I could find, plus my new developments.
One of the things that I've always wanted to add to xearth is the ability to "wrap" an arbitrary image around the Earth. There are loads of images suitable for projection onto a sphere, images of the Earth of all kinds. Here is the original xearth green-and-blue image (click for a larger view):
I finally (a decade later) got around to working out all the spherical trigonometry necessary to project images onto the xearth image. Here's a sample of what xearth can do now:
The maps don't even have to accurately reflect reality. Here is one from a 1678 world map:
Before I could do this with xearth, I also had to add the ability to create JPEG images (I added PNG while I was at it), and refactor some of the internal code to deal with true colour images instead of just palette-based images.
The code to do this is in the xearth repository on Github now. It's not ready for release yet, but feel free to fork and play with it.