SolidWorks eDrawings - SolidWorks offers complete 3D software tools that are easy to learn and use, and work together to help you design products better.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
SketchUp - 3D for Everyone
FreeCAD - An open-source parametric 3D modeler
SketchBook - SketchBook is a professional drawing or painting application that allows designers, architects, and concept artist to sketch their ideas and create adorable illustrations in no time.
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming