Analog computers coming back into vogue?

Analog computers coming back into vogue?  Well, maybe.  New metamaterials are providing opportunities to build components that perform basic analog computation (amplify, invert, add, subtract, multiply, divide, differentiate, integrate, etc.) with light, rather than electricity.  These could be used either directly as an analog computer, or indirectly as components in a light-based digital computer (much as transistors, resistors, capacitors, and inductors are used to make electronic computers).

Back in the '70s, when I was in the U.S. Navy, our ship still had quite a few analog computational systems still on board and in use.  The biggest, baddest of them was the all-analog fire control computer that ran the Terrier anti-aircraft missile system that was my ship's primary defensive weapon.  These analog systems were electro-mechanical beasts, full of precision electronic components, synchro motors, gears (some of them very complex), and oddly shaped cams that implemented arbitrary math functions.  Maintaining those computers was a never-ending job, mainly involving cleaning (dust and dirt actually affected their accuracy!) and lubricating.  A few systems also had electronic calibration that needed regular tuning.  But...these systems were (at that time) smaller than digital systems with the same capability, and in certain cases were faster.  These days a digital computer would win the race hands down, but back then, when our mainframe had a blazing 100KHz clock, an analog computer doing a few multiplies, divides, and differentiations, would beat the digital computer handily...