Last month, someone got the crazy idea to put Journey's protagonist into The Elder Scrolls IV: Oblivion. Granted, this isn't that offbeat an idea when you look at the larger modding context for the game -- my Internet license would be revoked if I linked to some of the sketchier stuff -- but somehow, we missed its arrival.
Journey developer thatgamecompany picked up on it, making today's rather sad videogame news cycle slightly less bleak. Natterforme, the creator of this novel project, has instructions at the first link. Shouldn't be too tough to implement if you have some prior experience with Oblivion mods.