Related context — after Frankel was kicked out of government work for political incorrectness in the 1950s, he designed the LGP-30 (the computer Mel Kaye famously programmed) and the forgotten Smith-Corona Marchant Cogito 240SR, on which project Tom Osborne was inspired to develop what eventually became the HP 9100, the foundation of the line of all of HP's programmable RPN calculators, and in some sense one of the first personal computers, shipping in 1968: http://www.hp9825.com/html/the_9100_project.html