EnTT - Header-only C++ game development library with innovative ECS (Entity-Component-System).
Unity - The multiplatform game creation tools for everyone.
Entitas - Entity Component System Framework for C# and Unity
Godot Engine - Feature-packed 2D and 3D open source game engine.
EntityX - Fast, type-safe C++ ECS (Entity-Component System).
Blender - Blender is the open source, cross platform suite of tools for 3D creation.