The “Outside the World Sphere View” is an undocumented effect used by e-On in several of their scenes.  If you have your camera at the center of the World Sphere and load an atmosphere you like; then do a simple render. 

 

Then Move the Camera outside of the World Sphere, the circular shaped pattern surrounding the ground plane, move the camera away by at least one length of the width of the World Sphere.   

 

Sometimes I go two lengths for a very large cloudy panorama.  Then do another render of the scene and you will see the difference.  The atmospheres shrink and the clouds appear very small, which allows you to add a number of additional cloud shapes that you could not have added when inside the World Sphere.  You can get some very complex looking atmos with this approach.  

 

http://www.renderosity.com/mod/gallery/index.php?image_id=1535452&member is an example of the complex cloud shapes you can add.  I was one and a half times the distance outside of the World Sphere.  

 

Another simpler scene was Autumn Comes to the Quarry, and DEP 10.  The atmosphere in DEP 10 was originally based on the atmosphere End of Time.  I added a few low level clouds to get an interesting look.  You can get very creative with all of that new space to work with.

 

Mind you, you will have to have your terrains and other objects outside the box as well and close to the camera.  

Galaxies are a whole new ball game and the distances can really get interesting, 100’s to 1000’s of units.  Makes for some nice Nebula clouds at those distances.

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