Cat’s Cradle:
I think Vonnegut does similar also at the start of Slaughterhouse Five IIRC.
In these examples, the breaking of the fourth wall comes when the author gives a command to the reader. “Call me Ishmael.” “Call me Jonah.” “Listen”:
Also, in Slaughterhouse Five, the first chapter is not really part of the story at all. Rather, the narrator (apparently meant to be Vonnegut himself) explains to the reader how he came to write the story. Then, in Chapter 2, the story actually begins.
I just found the full text of Slaughterhouse Five on-line, here (PDF), and skimmed the first chapter.
It’s much longer that I had remembered, and it’s clearly meant to be autobiographical in Vonnegut’s own voice, telling something of his experience in the war and reminiscing with a friend about it, whose wife didn’t approve of war stories that glamorized war, and how he thus came to write the rest of the story in the way that he did. The first word of the second chapter is a command to the reader: “Listen:”
ISTR that in The Book of Merlyn by T. H. White, Merlin, toward the beginning, makes a few remarks about how best to proceed with the education session so as to make matters easier for the readers.
Much to Arthur’s consternation (“We’re in a book?”).
THAT, my friends, is how you break the fourth wall. 
One of the people who noted that was me. I am aware that there are many examples of first person narrators “breaking the fourth wall”. What I am disagreeing with is the claim that ALL stories written in the first person use this device.
Philip Roth, The Great American Novel:
Isaac Asimov’s Murder at the ABA. See if you can follow this… or if I can explain it:
This is a first-person mystery where the protagonist, Darius Just, is a writer who gets involved in a murder case while attending an American Booksellers Association convention. Asimov himself is a minor character in the story. However, it’s stated that Just gave Asimov permission to write the book. So it’s a novel written by Asimov, from Just’s perspective, with occasional footnotes by “Just” criticizing the way Asimov described certain events, followed by rebuttals by Asimov insisting that the story is accurate.
(The character of Darius Just, incidentally, was loosely based on Harlan Ellison, and later reappeared in one of Asimov’s Black Widowers short stories.)
Ah, yes, I see. I agree, and in fact, some first person narrators are strangely omniscient.
I just thought of another scene in Slaughterhouse Five in which Vonnegut injects himself into an otherwise totally surrealist story. The story is told entirely in the third-person omnicient point-of-view, but here he injects one paragraph in which he, speaking as the author, speaks in the first person directly to the reader.
Billy Pilgrim, the main character, is a POW in Nazi Germany during WWII. The POW’s, or some of them anyway, have just been given a good meal (an entirely unusual thing), and they all pigged out and now have Montezuma’s Revenge en masse. Billy encounters a group of POW’s having a shit-fest in a makeshift latrine:
Note the peculiar mix of first-person and third-person in that last line there.
Another Stephen King or two:
In “The Mist,” David (the narrator) is writing down the story, and includes something along the lines of “is there anybody reading this?”
Also in the story “The End of the Whole Mess,” the narrator says something very similar at a couple of different points
I don’t see The Martian as meeting these criteria, he’s writing a journal. Well, recording a journal.
The French Lieutenant’s Woman. Halfway through the book, Fowles comes to a screeching halt and says, basically, “Now, that’s what would have happened if such and such had been done, but things didn’t go that way, so now let’s find out what actually happened”, and he rolls back the whole plot.
In Spike Milligans novel * Puckoon * the character Dan Milligan has a conversation with the author complaining about his badly written legs . In compensation he is given an emergency word to get out of trouble which is eventually used but not to the desired effect.
There’s a Dirk Pitt novel in which Clive Cussler makes an appearance at Pitt’s (I think ) wedding .
In Bright Lights, Big City Jay McInerney addresses the reader in second person for the entire novel, telling you each crazy thing you’re doing.
I see two cases in all the offerings here. One is the rather standard literary device in which the narrator of a first-person story speaks/writes as if the work is a diary or journal, and assumes some Dear Reader will be reading it.
The other is where a character in a fictional setting turns and begins talking to the reader in ways that is not narrator-to-reader.
A lot of Travis McGee’s asides are more like the latter than the former - he doesn’t seem to think he’s telling the story to a journal or reader, but pauses to explain his thought process (usually about social issues) as if he is lecturing or telling the reader directly. Maybe that’s a third case.
That’s standard second person. I’ve never heard it called breaking the fourth wall before.
I always assumed parts of Fight Club did this. “I am Jacks…”
Also High Fidelity the random lists of things seem to be directed to the reader, not part of the character’s inner monolog.
Flann O’Brien : At Swim-Two-Birds. 1939. Amongst others. I prefer The Third Policeman, and therein, dear reader, the physiological, psychological and scientific insights of de Selby.
Somerset Maugham writes himself into The Razor’s Edge…even giving himself some heterosexual encounters I believe.
Based on your link, I wound up buying this for my four year old. Out of print (I believe) but easy enough to find for 1¢ + $3.99 shipping “used” on Amazon.
The little guy liked it so thanks for bringing it up!
(Seeing Spiegelman’s distinctive artwork in a children’s book after Maus was a little weird for me)