How did you go down the rabbit hole? For me it was in prehistoric times when I worked for a time share that was a dealer for Xerox 820 computers. https://en.wikipedia.org/wiki/Xerox_820#Disk_storage Xerox came out with an updated main board and did not want the original one back. So .... https://en.wikipedia.org/wiki/Ferguson_Big_Board A home made plywood case, with a power supply and green monochome monitor was coupled with an 8" floppy drive. Running CPM with the WordStar word processing system and the original Colossal Cave text based adventure game, I was set to go. You could hear the floppy seeking from across the room. Great fun!