SketchUp - 3D for Everyone
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
MakeHuman - MakeHuman is a free, open source, interactive modeling tool for creating custom 3D human characters.
DraftSight - Discover Dassault Systèmes®' DRAFTSIGHT™ Professional CAD software that lets you create, edit, view and markup any kind of 2D drawing. Learn more here.
ZBrush - ZBrush is a digital sculpting and painting software solution.