Ran across this randomly while searching for something else: Audioverse is “an interactive fiction framework” that includes rigorous modeling for ambient sound effects. The screenshot looks severely old-school to my eye, and I haven’t gotten the downloadable sample file to run, so I have no idea what it’s like in practice, but I confess I’m intrigued by the description. I have generally tended to think that a heavily sound-based approach to IF runs into problems because it’s hard to sync the real-time nature of sound with the turn-based text — but I haven’t tried something like this, and it might be interesting.