SolidWorks eDrawings - SolidWorks offers complete 3D software tools that are easy to learn and use, and work together to help you design products better.
SketchUp - 3D for Everyone
Autodesk Revit - Autodesk Revit is building information modeling software for architects, structural engineers, MEP engineers, designers, and contractors.
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.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
PTC Creo Sketch - Creo Sketch is an easy to use 2D CAD application for capturing and creating new 2D freehand concepts which is available on PCs, Macs, and iPads.