I am a huge retro fan. I go by the motto "Old computers never die, their users do."
Every computer that was ever made, is still just as useful as it was the day it was put into operation, for some reason. Okay, its not absolute: but as a first principle, computers are as useful as the user decides they are. Its just a decision.
I love my old machines. Its so fun, as a hacker and grey-beard developer who has seem some shit, to go back to the great ol' days of .. say .. CP/M .. and sit down and noodle on some code or other.
Or, hack around with tools like "8-bit Unity", which is an attempt to build a high-performance engine for as many 8-bit machines (6502-based) as possible, with modern toolsets. Actually, this is bonkers enough I just have to make sure you know about it, in case you don't already:
http://8bit-unity.com
One set of tools, tons of machine targets, and .. who knows what these systems will get up to, when this gets into there right hands ..