The hacker is a 10-year-old girl who goes by the name of CyFi, according to a story from PC World. She presented last weekend at DefCon Kids, a children-oriented offshoot of the annual DefCon hacker conference that took place in Las Vegas. And the exploit she found is a pretty simple one: by messing with her mobile device’s clock, she was able to alter the in-game time in her farming simulation app (read: FarmVille or a similar game), thereby shortening the time the game required her to wait for her crops to grow. The hack works...