VeroRoute - Cross-platform software for producing Veroboard (stripboard), Perfboard, and single-sided PCB...
Unity - The multiplatform game creation tools for everyone.
Virtual Breadboard - It is a circuit simulator on a virtual breadboard.
Godot Engine - Feature-packed 2D and 3D open source game engine.
KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
Blender - Blender is the open source, cross platform suite of tools for 3D creation.