HeroMachine - Create your own super-hero, sci-fi, or fantasy character sketch
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Avatar Maker - Create your own avatar online
Autodesk 3DS Max - 3ds Max is software for 3D modeling, animation, rendering, and visualization. Create stunning game enrivonments, design visualizations, and virtual reality experiences.
The Character Creator - aims to provide a fun and easy way to help you find a look for your characters.
ZBrush - ZBrush is a digital sculpting and painting software solution.