By the year 2020, the basic memory components of a computer will be the size of individual atoms. At such scales, the current theory of computation will become invalid. A new field called "quantum computing" is emerging that is reinventing the foundations of computer science and information theory in a way that is consistent with quantum physics - the most accurate model of reality that is currently known. Remarkably, this new theory predicts that quantum computers can perform certain tasks breathtakingly faster than classical computers, and, better yet, can accomplish mind-boggling feats...