On 2009-02-23, wrote:
RSTS/E, RSX-11, RT-11, TOPS-10, TOPS-20, VMS...

PDP-6, PDP-8, PDP-10, PDP-11, VAX...

All of those are emulated, and the smaller PDPs and VAXen aren't all
that hard to come by as actual hardware. (I even have a MicroVAX of my own).
The old IBM systems are emulated by Hercules (so EBCDIC is also something
that's available in an emulated system).

While not every hole will be filled, any system that has a modicum of
popularity will be emulated, especially the type of machine people had
at home in large numbers. For example, the Sinclair Spectrum (a popular
1980s 8 bit system in the UK) is emulable on most modern platforms from
the Nintendo DS and Wii to a 64 bit UltraSPARC server, and almost the
entire software catalogue of well over 10,000 items of software is
avaialable on modern media.

--
From the sunny Isle of Man.
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