Though not since 2011, Air traffic Control Input/Output Processor [IOP](http://vipclubmn.org/aircontrol.html)s ran 40 years from 1971 to 2011 - so decommissioned not that long ago but did start in a relatively primitive digital time and had a long run.

The [Input/Output Processor](http://vipclubmn.org/ATCntl/IOP%20data%20sheet.pdf) was an array of maybe 200 cards.  Each consisting or what counts today as a few [gates](https://en.wikipedia.org/wiki/Logic_gate) to a few hundreds.  Its computation strength was in its parallel I/O processing.