I wish to read fiction that has a very high ratio of exposition imparted to amount of actual writing.
My idea of an Ur-example of this would be entirely dialog, with no non-dialog descriptions. Of anything. It would depict a complex world/universe, set of characters, language tone, detailed history, visuals, actions taken and events unfolding, with as little non-vital wordage as possible.
The author that comes to mind who does this best is William Gibson, where he can use a three word phrase to make it seem like you've known this intricate, novel, yet entirely brand new concept for years. His opposite would be someone like Neal Stephenson. Love the guy, but brevity in exposition is not his forté.
I'm more interested in the structure and process of this kind of writing, so it does NOT necessarily need to be the most enjoyable thing one has ever seen, though pleasant reading would be nice. Stunt writing (i.e. something done just to see how workable this concept is) would be interesting, too. Writing education material would be OK, but not ideal.
This probably happens most in short stories, but I'd rather read novels. I would prefer hard science/speculative fiction over other genres, but anything you've got is great.