3D-Coat is the one application that has all the tools you need to take your 3D idea from a block of digital clay all the way to a production ready, fully textured organic or hard surface model.
What's new in 3D-Coat
Adaptive Decimate Brush: reduce without fear of loosing detail http://wp.me/petJN-zY
Snake/Spikes/curves/Muscle/Toothpaste tools are supported in surface mode too (even faster) - http://bit.ly/vMlC3X (booleans of course). It is 160 k model. To get same in voxels you need probably millions. Of course that spikes/curves are not separate pieces but merged into object - look a little manual smoothing near some spikes.