Good reminder to check back on House of Leaves. Didn't like it but it keeps nagging at my brain, I must have missed something.

It's quite exhausting to read though.

Although thinking about it now I remember feeling the author being kind of cruel in making things hard to read/understand with that as the purpose (the real excentric stuff at the end), it put me off. Maybe I just don't like it.

This is essentially what Myst is, isn’t it? It has a clear start and end. But the books are visited in any order. And as a bonus; the pages of the red and blue books are reassembled in any order.

These rely so heavily on physical layout that e-readers basically ruin the whole experience.

I did a story once where the the action gradually departed the main text and shifted into footnotes on the page.

The whole story was silly, and that particular page was "stunt writing", so I'm not quite sure that it qualifies.

There is also: https://en.wikipedia.org/wiki/The_Manuscript_Found_in_Sarago... which was made into an interesting movie: https://www.imdb.com/title/tt0059643/

That's more about recursion than anything.