Psychiatric Evaluation's probably a bit better as an idea than an actual game, but wow, what a neat idea. It begins as a text adventure - because obviously, crazy people see only in eloquent prose - but as your sanity improves, the game evolves. So talking to a doctor once transforms your mad world into an ASCII symbol jambalaya, twice yields a top-down Atari-style adventure, and three times bumps the graphical fidelity up to something you might have seen (and heard) on a Super Nintendo. What's even more impressive, though, is how that clever representation of your sanity gets weaved into this psycho-not's central puzzle.
Before I explain, I actually recommend just playing through Psychiatric Evaluation yourself. It was originally made for Ludum Dare, which is why it's not particularly fleshed out. But that also means it's over in the blink of an eye, so there's not much of a time commitment involved.
Anyway, your objective is to escape from the asylum, but you can only accomplish some of the necessary steps in certain interfaces. So moving through the world is far easier with actual graphics, but you can't talk to friendly, password-dispensing ghosts unless you're stark, raving mad. Granted, it all ultimately boils down to (literally) bouncing back-and-forth between madness-curing doctors and sanity-sapping patients, but some of the nuances are clever. For instance, a major puzzle solution draws on obtuse text adventure logic to such a degree that I had to look up a walkthrough. Maybe it's just bad game design, but I dig it regardless.
Definitely give Psychiatric Evaluation a go, if it sounds like your kind of thing. If you even exist. If you're not just the final sanity stage in a sequel to the game you just read about.
(Props to Gameological Society for digging this one up.)