Anybody awake knows Moore's Law--or should. At a constant price point, computer chips get twice as good every 18 to 24 months. That's not exactly what Gordon Moore wrote in 1965 when he laid down his law. Physicists don't use words like "good." No, Moore was thinking about transistor densities on silicon chips. But during the 1980s, thanks to the amazing rise of the personal computer, Moore's Law took on a larger meaning. It became the symbol for exponential gains in technology. For example, I bought my first hard-disk drive in 1984. It stored 20 megabytes and cost $500. …