Algodoo - Algodoo is a 2D simulator freeware product designed as a physics learning tool. It was originally created by Emil Emerfeldt as part of his master’s thesis in 2008. Read more about Algodoo.
Unity - The multiplatform game creation tools for everyone.
SimPhy - Interactive 2D & 3D Physics simulation software
Godot Engine - Feature-packed 2D and 3D open source game engine.
Physion - Physics Simulation Sandbox
Blender - Blender is the open source, cross platform suite of tools for 3D creation.