I love this kind of free software (or open source) project.
It is a hard work for several years.
I think that the goal or finish of this work is the engine and a new (similar to old close game) set free assets (sprites, 3D models, maps, music...). And I know few projects in this point, OpenTTD and FreeDoom.
OpenRA (Command & Conquer), CorsixTH (Theme Hospital), ET: Legacy (Wolfenstein: Enemy Territory) and FreeCiv (Civilization) are the examples I have spent the most time playing. I know there are others targeting games like Age of Empires and Heroes of Might and Magic but I haven't played them and I'm not sure if they are as mature.
It is a hard work for several years.
I think that the goal or finish of this work is the engine and a new (similar to old close game) set free assets (sprites, 3D models, maps, music...). And I know few projects in this point, OpenTTD and FreeDoom.
Are there more projects in this point?