Whither Moore's Law; Introducing Koomey's Law
Joining the ranks of accepted submitters, Beorytis writes "MIT Technology review reports on a recent paper by Stanford professor Dr. Jon Koomey, which claims to show that the energy efficiency of computing doubles every 1.5 years. Note that efficiency is considered in terms of a fixed computing load, a point soon to be lost on the mainstream press. Also interesting is a graph in a related blog post that really highlights the meaning of the 'fixed computing load' assumption by plotting computations per kWh vs. time. An early hobbyist computer, the Altair 8800 sits right near the Cray-1 supercomputer of the same era."
My favorite example of computing (in)efficiency is the USAF's SAGE bomber tracking computers introduced in the 1950s. These vacuum tube machines had CPU horsepower probably in the same ballpark as an 80286, but could draw more than 2 megawatts of power each. They didn't decommission the last one until the 1980s.