The Postman Always Rings Twice - James M. Cain (1934, U.S.)
Dashiell Hammett's blurb practically says it all: "a good, swift, violent story." It's not really shocking for our Tarantino-ed sensibilities and there are a few ridiculous aspects (e.g. the puma), but it has some clever literary devices and I thoroughly enjoyed it. The ending certainly has existential resonance and it's not difficult to see the link between this work and The Stranger (which Camus modeled after this novel).
The Day of the Owl - Leonardo Sciascia (1961, Italy)
Described by some as a "metaphysical mystery," I would probably just call it a "literary mystery" - it has beautiful prose and presents an accurate (and by now perhaps even clichéd) view of life in a mafia-controlled Sicilian town, but has no real philosophical weight. To be fair, this novel was Sciascia's first foray into detective fiction, and later works are often said to be more complex.
Three Exemplary Novels - Miguel De Unamuno (1920, Spain)
Basically made up of three longish short stories, not novels, which are very similar to the stories collected in Ficciones and fall somewhere between them in terms of quality - better than La Tia Tula but not as good as his best short work "San Manuel Bueno, Martyr" (and certainly not as complex or interesting as his novel Mist). All three stories have biblical echoes, and are fairly bare in literary terms - there's hardly any description of atmosphere, space, or time, and the characters' psychology remains mostly unexplored - so that they feel more like extended parables than fully fleshed-out stories.
Dolly City - Orly Castel-Bloom (1992, Israel)
I had never read anything by Castel-Bloom before and try to avoid back cover blurbs, so I was genuinely shocked by this novel. It's sort of like a particularly vicious Donald Barthelme story - it has its own internal logic, divorced from our reality but related and constantly commenting on it (other works that came to my mind while reading include Harry Mathews's Tlooth, and in some particularly surreal sections even Ben Marcus's The Age of Wire and String).
Castel-Bloom is often named alongside Etgar Keret as a representative of a certain type of Post-Modern Israeli literature, and there's certainly a similarity of tone and subject matter between the two. I read the novel in Hebrew, but Dalkey Archive Press is planning to release an English translation in Fall 2010 as part of its new Hebrew Literature Series.