So remember this ancient game called Skyrim? Yeah, the one with mods that your PC couldn't run.
A couple of those modders had been working together for five years to produce an entirely new game based on Skyrim's engine. From a whole new map, new quests, completely reworked skills, lots of new NPCs, and, oh yeah, voice acting (Good voice acting. Not as good as a studio made game, but pretty damn good).
Also, it's completely free of cost. A model that the modders aim to continue in their future releases.
It's called enderal, check it out at
http://kotaku.com/enderal-is-more-than-a-mod-it-s-a-whole-new-skyrim-1785370151