[kwonkicker]

Blender and Unreal Engine comes to mind. Similar formula.

[jcparkyn]

I wouldn't describe blender as following this formula. The only thing they sell (last time I checked) is blender studio, which as far as I'm aware is more just another way to donate while getting some things in return.

[ralusek]

Blender is open source and free, Unreal is paid on the backend.