Esko Studio - Studio is a unique set of tools for 3D packaging design made specifically for packaging artwork...
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Boxshot - Virtual 3D packaging mockup and rendering software.
FreeCAD - An open-source parametric 3D modeler
Placeit - Generate realistic product shots in seconds
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming