FreeCAD - An open-source parametric 3D modeler
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
VARKON - Varkon is a very powerful parametric 2D/3D CAD, modeling and application development tool for...
ZBrush - ZBrush is a digital sculpting and painting software solution.
ArCADia-Architecture - ArCADia-Architecture is a revolutionary component for the instant creation of architectural documentation and object drawing.
Cinema 4D - Cinema 4D is a 3D modeling, animation, motion graphics and rendering application.