I tried to keep my head out of the clouds, but you raise such interesting possibilities, eonite:)
The lonely clouds you and chipp showed are so cute...
It occurred to me that you can use the same tooth node to make a hole in the layer of clouds - just need to add an 'invert' math node after the tooth node.
Could come useful when you want a hole in the clouds for god rays to come through.
I know of another method to create a hole - you put a large object through the clouds, make it invisible and turn on dissolve near objects for the clouds. But it appeals to the mathematician in me to do it with a function rather than a (virtually)real object:)

I havnt tried it yet - why let reality spoil a good idea first thing in the morning...

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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