I'd say:
PCengine/turboGraphX, but Fast already mentioned it.
Philips CD-i
Chip-8
Thomson MO5 (hey, my first computer!)
Dos-box (does that count? I suppose it's your "MS-Dos" folder)
ScummVM (more like interpreter than an emulator, it doesn't emulate a system but only the data used on it, but does the same job too)
Exult (yep, more like a recreated game engine around existing data like ScummVM, it works like an emulator as you need original files, but for a single game : MsDos Ultima 7)
I don't know if you have these :
Sony
Pocket Station
Sega VMU (Sega Visual Memory Unit, it's the Dreamcast memory card device)
Sega
VMS (Visual Memory System, VMU emulators? look for
SoftVMS)
Some more emulators for windows
https://www.zophar.net/windos.html