Here is another rock flying in the sky.
I dit it with Cycle engine using only procedural textures. I was thinking of building something on top of it or to add some trees or grass but I think it is easier to use without vegetation.
There are lots of details on this structure for I intended to make quite a huge rock. And the texture should look fine even if you zoom in.
If you intend to make an animation, do not use my post processing for I made it specifically for stills.