Blender - Blender is the open source, cross platform suite of tools for 3D creation.
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
FreeCAD - An open-source parametric 3D modeler
DVDVideoSoft Image Convert and Resize - Free Image Convert and Resize is a compact yet powerful program for batch mode image processing.
meshmixer - meshmixer is an experimental 3D modeling tool for making 3D mashups without too much hassle.
Ralpha Image Resizer - High-speed image batch conversion tool