Jonathan Guberman of Site 3 coLaboratory hackerspace in Toronto has created an Arduino-controlled mechanical typewriter that can type on its own, detect what is being typed on it, and run text-based interactive fiction games such as the classic (and to most, all but forgotten) Zork.
"Introducing the Automatypewriter, a new way to experience interactive fiction! It's still a little rough around the edges (in particular, you can see that the spacebar sticks a little, and the whole thing needs to be tidied up), but you get the idea: the Automatypewriter is a typewriter that can type on its own, as well as detect what you type on it. By reading what it types to you and responding, it can be used interactively to play a game or participate in a story (in this case, Zork)."
Project build details here.