I just found this - might be of use to a few people.
To quote directly from the site…
Fracplanet - Generates fractal terrain or planets.
Fracplanet is an interactive tool for creating random fractal planets and terrain areas with oceans, rivers, lakes and icecaps. The results can be exported as models to POV-Ray and to Blender, or as texture maps for more general usage. The code is licensed under the GPL. It uses Qt and OpenGL.
Ubuntu/Debian package found via
P.S. This looks pretty neat too.
Evolvotron - “Generative art” software to evolve images.