Using Sculptris to create high-resolution version of your models
From Mount&Blade Modding Wiki
Here we go... A screeny of Sculptris is worth a thousand words ;)
It has also the ability of unleash your creativity directly into the normal map by sculpting fake volumes in the Paint mode and exporting it.
I want to public ally greet drpetter from here for his amazing work in the app and his recent work at Pixology, makers of Zbrush!