We might generate a taxonomy of Dead Media which classifies each clearly according to its origin, or function, or demise. But there is something beyond these functional considerations which makes us circle around the elephants' graveyard of Dead Media. I would suggest that Dead Media are signifiers for particular moments, for particular forms of experience. This is not to say that necronauts flee into dusty closets to escape the present. I'm all for excluding astrolabes, theodolites, the Antikythera Device, analog computers, and so on from this discussion.
Computers used for communication are central to the study of media.
Computers used for ballistics calculations are not. Now, if it so happens that somebody somewhere once came up with a way to transmit messages via dice, using some code where the numbers represented something other than numbers, I would say that is interesting enough to include in in our list. Another reason to exclude most scientific instruments and early computing devices is that sources on their history are readily available. I see a lot of re-inventing of the wheel going on in this list. That reflects sloppy and inefficient research.