...those being the criteria that someone I know (CL) came up with when I asked her for some parameters to her request for book recommendations (this being a person who I don't know well at all, either personality or lit tastes-wise). So this is what I came up with, off the cuff:
Italo Calvino - Invisible Cities
A series of graceful, poetic meditations on 'invisible cities' - imagined cities ostensibly visited by Marco Polo and then described by the great explorer in an extended philosophical conversation with Kublai Khan. I've never read anything else like it; to call it a 'novel' does its uniqueness a disservice.
Thomas Pynchon - The Crying of Lot 49
A warning: Pynchon is certainly not for everyone! But Lot 49 is his most accessible book and probably his best, an absurdist, crazily unravelling and frequently, blackly hilarious postmodern detective story in which what is at stake is nothing less than the very possibility of communication, meaning and truth itself.
Haruki Murakami - Hard-Boiled Wonderland and the End of the World
For mine, Murakami is the single writer to have best synthesised the competing urges and joys of 'literary' and 'genre' fiction to produce something wholly original and great. Hard-Boiled Wonderland is probably my favourite - it's clever, cool, lucid, heart-breaking, inspiring. It's about the nature of consciousness and how that relates to what we think of as reality; it's also a gripping adventure story.
Nicole Krauss - The History of Love
A more modest book than the others I've mentioned here, and also more recent, but a substantial one nonetheless. It deals with family, loss, and the nature of human connection, and it builds to an almost unbearably touching ending that literally induced chills down my spine in the final pages.
Andre Gide - The Counterfeiters (Les Faux-Monnayeurs)
Another that isn't for everyone, but The Counterfeiters is a masterpiece. Coolly amoral, ironically intellectual, acerbically witty - a French novel par excellence, but what a novel! Set in the early part of the 20th century, it follows a large cast of characters - schoolboys, intellectuals, artists, and co - as they mislead and misunderstand each other, all the while itself interrogating its own nature as a work of literature through a series of complex, interwoven metafictional gestures.
Mikhail Bulgakov - The Master and Margarita
A riotous, generous satire of life in Stalinist Russia. Its main narrative involves the coming to Moscow of the Devil at his most urbane, with accomplices including a heavy-drinking, chess-playing black cat, and the social havoc that he then wreaks amongst polite society; that's intercut with a parallel retelling of the story of Christ and Pontius Pilate and with an epic love story. All the Big Themes, in other words - religion, art, love, politics, etc - but it's extremely readable and very funny.