I recently received a free one of these at a garage sale. The daughter of the nuclear physicist who used it during his career had it out and said I could have it for $0.50. I didn’t have small bills or change, so she just gave it to me.

I knew “of” HP calculators, but hadn’t yet deep dived into _why_ they were cool. This kicked it off for me. It’s probably on the original battery.

I suspect maybe she knew it was worth a fair amount, but didn’t care. She seemed very zen with the idea of reducing the amount of unused items in her life. It was a very cool, eclectic sale by two home-based artists.