Blender - Blender is the open source, cross platform suite of tools for 3D creation.
AutoCAD Electrical - AutoCAD Electrical design software is electrical engineering software for electrical CAD.
FreeCAD - An open-source parametric 3D modeler
QElectroTech - QElectroTech is a free software to create electric diagrams.
Sculptris - Sculptris: Enter a world of digital art without barriers.
SolidWorks Electrical - SOLIDWORKS® Electrical solutions simplify electrical product design with specific tools for engineers and intuitive interfaces for faster embedded electrical system design.