More Computing Efficiency

Not only have computers gotten exponentially faster per dollar, they've also gotten amazingly more energy efficient:

Over the past 60 years, the energy efficiency of ever-less expensive logic engines has improved by over one billion fold. No other machine of any kind has come remotely close to matching that throughout history.

Consider the implications even from 1980, the Apple II era. A single iPhone at 1980 energy-efficiency would require as much power as a Manhattan office building. Similarly, a single data center at circa 1980 efficiency would require as much power as the entire U.S. grid. But because of efficiency gains, the world today has billions of smartphones and thousands of datacenters.

Of course an iPhone would have been impossible to build at any price in 1980 and even if possible would have required the space of an entire Manhattan office building!