I really love the work of Aris Kolokantes and find that his sculptures make really dynamic subjects for speed sculpts within ZBrush. I chose this sculpture below for reference and inspiration. Check out http://ariskolokontesart.blogspot.com/
I started the model with zspheres, then once I reached a certain subdivision level I rebuilt the mesh and projected all the exisiting detail on to the new surface. This allowed me to get even greater details for the finishing touches.
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