Hello ZBrushers freaks
Try these incredibily strongest free programm ! Capow 98 http://www.mathcs.sjsu.edu/capow/
Math curve to yellow submarine 
Interface is rustic but…
With it create much colored image in 2D or 3D and import it in Zbrush.
And with the Alpha Century method you will make another crazzy Zworlds
Pilou flashy1970