FreeCAD - An open-source parametric 3D modeler
KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
VARKON - Varkon is a very powerful parametric 2D/3D CAD, modeling and application development tool for...
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
ArCADia-Architecture - ArCADia-Architecture is a revolutionary component for the instant creation of architectural documentation and object drawing.
QUCS - Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit.