Computers, like guns, isn't something that can be invent again. Improve and innovate upon, but never again will it be invent. Fundamental gun features have stayed pretty much the same since the 15th century, that is create combustion and propels a small metallic object from the resulting explosion to inflict damage on a target. Sure, guns can now fire without utilizing gunpowder, have magazine action behind the trigger and shortening the length of the gun in general, fire bullets at a much much faster velocity, but the fundamental of a gun still stayed the same. Any new invention that possess this fundamental rule isn't a new invention, it's an improvement on the gun.