There are a good number of old devices that still have a devout following. For MS-DOS you might check out e.g. Planet X3 [1]. Or how about Super Boss Gaiden [2], a game for a prototype console of which (AFAIK) only one unit is in existence (but you can play the game on an emulator, which apparently exists for this obscure console).

[1] http://www.the8bitguy.com/product/planet-x3-for-ms-dos-compu...

[2] https://playstation.fandom.com/wiki/Super_Boss_Gaiden