I'm pretty sure a TI calculator fits the bill for tech heirloom. It's very basic, just an Z80 cpu and a small LCD display. It's rugged and can last. Even with b

I'm pretty sure a TI calculator fits the bill for tech heirloom. It's very basic, just an Z80 cpu and a small LCD display. It's rugged and can last. Even with being outdated tech, they sell for as much as when they first came out and could definitely be "inheritable". And, because it doesn't aspire to be a general purpose computer, just do some fancy math, it's not going to be outdated (unless you count ubiquitous cell phones)