My son is into retrocomputing, mostly using older hardware I have from when I was younger, and we have a stack of old compaq desktops where you can't access the bios because it requires a specific floppy that is nearly impossible to find online. This is 486/pentium era stuff, the older stuff is even harder to find.

I've been looking for a DEC terminal with Sixel, Tektronix and ReGIS graphics for a while, with zero success. They weren't rare at all - they were a massive success, and, yet, it seems almost all ended up in a recycling facility or an e-waste dumpster. Many other terminals emulated them and expanded on their feature set.