FreeCAD - An open-source parametric 3D modeler
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
Dock Designer - Customized to the specific building rules of dock building companies, Dock Designer enables visual design in 2D where you can see your dock design in 3D and have instant access to accurate estimates, parts lists, blueprints, and much more.
SketchUp - 3D for Everyone
KediCAD - CAD/CAM/ FEA software for Linux
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.