I used NWDA's planet pack, altered the surface here and there (no snow, better sand/desert color) and added a ring of marbles.
Its not real looking. But it is very cool! I like this kind of graphic work. There are a lot of uses for this style.
That is really good and I like it a lot... infact, to me it conjours-up the following,
Drifting peacefully through the tenuous outer wisps of the Pleiades Nebula the planet and its inhabitants were blissfully unaware of the arrival of a swarm of self-replicating Von-Neuman probes relentlessly expanding ever outwards in their quest to colonize the galaxy.
I hereby rename the spheres : "Von Neuman Probes" ;)
Inspires me to build more.