Epic Games are currently streaming a talk where a new Unreal Tournament has been confirmed, using Unreal Engine 4 and it will be free. Not free to play, or pay to win but totally free. The game start development from today and as it moves forward from Alpha to full release players will not be charged for the experience. It has been confirmed for PC, Mac and Linux, while a version for Xbox One and PS4 have not been mentioned at all.
Epic wants to work with community to help build levels, weapons and mods. The developers will be interacting on the forums with everyone who wants to get involved and working through ideas. Developers that do decide to create content for the new Unreal Tournament can decide to give their stuff away for free or charge for it through a dedicated marketplace. If you want to get involved you need to go to the forums and create an account. You can then download the code and content for UE4 from Github.