This is my latest work: Atoll
I created the original terrain in Photoshop as a grayscale bumpmap. I then imported into Bryce where I eroded and added noise to the terrain. The rendering of the model was done in Terragen. And finally post production in Photoshop.
Other recent additions have been: New Tutorial: Tendrils:
Now you can create those trendy tendrils and tentacles without a 3D package.