Raul has stated a new project on voxel sculpting, as he mentions a good example of this in 3d-coat since this is a new concept of modelling/sculpting i downloaded the trial version of 3d-coat (available for win/linux/osx) and writhing 2 minutes was creating:
a underwater rock-formation. Admittedly i was using the materials and brushes supplied with 3d-coat.
The Voxel sculpting work-flow is such that as you extend the object it adds resolution to that extension. the result is that you never end up having a mesh with to low a resolution for your current brush to have effect. of course you can increase the inter resolution (using multi-res) however this will create lots of resolution were you don't need it thus slowing down your system.
