RealityMAX - RealityMAX is the most powerful free 3D design collaboration platform, 100% online. Cooperate remotely with your colleagues on 3D projects and easily share your work with clients. Create Web3D and AR experiences in a snap, without a line of code.
KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
Cadbull - Cadbull is a website that comes with an advanced collection of CAD blocks and DWG design, facilitating architects and designers to get done with their projects efficiently.
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
DWGFREE - DWGFREE is an online platform that comes with a comprehensive collection of CAD blocks that can be downloaded without the need for registration.
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.