A nice FOSS version of Minecraft I actually just heard about Minetest when flipping through a free and open source repository. That said  I am impressed with how many features Minetest has. It plays a lot like Minecraft to the graphics and gameplay  but it does offer extra modding features to extend things even more. Shoutout to the contributors to the Minetest project for making a cool open source version of Minecraft  and to more interesting things down the road.
March 24 2015