SketchUp - 3D for Everyone
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
SmartDraw - Instead of starting with a blank screen, SmartDraw gives you the exact template you need.
Autodesk 3DS Max - 3ds Max is software for 3D modeling, animation, rendering, and visualization. Create stunning game enrivonments, design visualizations, and virtual reality experiences.
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.
ZBrush - ZBrush is a digital sculpting and painting software solution.