I play video games for fun. Who doesn't? But there's only so many times you can play through a level on a three-year-old game before it becomes rote button-tapping: the interactive equivalent of bingeing "House" on Netflix. You know exactly how it's going to go. Enter the world of "mods." These are free patches fans create to expand the worlds of their favorite video games – sometimes for the better, and sometimes just for the weirder.