KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
Microsoft 3D Builder - View, capture, personalize, and print 3D models.
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
Infurnia Architecture Design - Infurnia is a powerful, multi-featured cloud-native Architecture solution that you can use to introduce BIM in your Designs, partner up with others using functions, and take care of the data in an effective way.
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.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.