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I had a couple including one USB one that I later modified to use to scan regular bar codes.
I pulled up Wikipedia to look up who created them, and apparently he changed his name after they failed. He was also on Curse of Oak Island searching for gold and was involved in ballot shenanigans in the 2020 US presidential election where he was notable for supposedly inventing a machine to find bamboo fibers on ballots.
I was in USA in the mid 80's, and bought a Radio Shack programmers calculator. I still have it, and it still works. batteries must have lasted for 5+ years, because we moved 5 years ago, and I'm pretty sure I didn't put new in while living here, and when I found it, the power was still on, and the clock ticking, buttons still working almost 40 years on now! Amazing... ๐
I keep it now as my best souvenir from that trip.