I have this OS-9 6809 development system bought many years ago for developing embedded software. It's a (AFAIR)G64 bus backplane with plugin cards; cpu, memory, I/O ... I even have some extra cards and most if not all of the manuals. Super machine, knocks the IBM PC with which it is roughly contemporary into a cocked hat.
I'd like to pass it on to a good home, I need the room, and it would be a crying shame to dump it. Anyone interested - I've tried old-computers.com but there seemed to be no interest, probably it's not a computer by their definition.