LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
OpenSCAD - OpenSCAD is a software for creating solid 3D CAD objects.
SketchUp - 3D for Everyone
SolidWorks - Dassault Systèmes SolidWorks Corp. develops and markets 3D CAD design software, analysis software, and product data management software. SolidWorks is the leading supplier of 3D CAD product design engineering software.
FreeCAD - An open-source parametric 3D modeler
BRL-CAD - BRL-CAD: Open Source Solid Modeling