Maria Gloria-Fernandez, one of the six main characters of Six Chances the webnovel, appears to be this. She is a pirate captain in the middle of looting a ship and is called out for the pirate that she is. Her response? "Haha, we're not pirates! We are adventurers!" It can be read here.
Emily Dorothea Seaton, protagonist of a series of mystery novels by Heron Carvic. She's not exactly out of it, but her thought processes are difficult for others to follow. Unlike other amateur sleuths, she has no idea she's involved in mysteries. Oh, and if you mean her harm, stay clear of the brolly....
Most characters in Alice in Wonderland count, but the Cheshire Cat is arguably the most famous. He's also a recurring character in the Thursday Next series, where he's portrayed as smart enough to manage a library containing every book ever written single-handedly, but still spends most of his time asking bizarre and irrelevant questions.
Animorphs: Tobias is one of those up until the end of the first book. After that his mind is much more 'down to Earth', the irony being that a lot of the time his head is up in the clouds, because he's a bird.
Anne Shirley of Anne of Green Gables falls victim to this moderately, especially in the earlier books. She just really loves living her own little fantasy world, a world where everything is really, really romantic. She asks Marilla to call her "Cordelia" rather than Anne upon their first meeting, claiming it sounded better. It's to the point of hilarity, really. She gets herself into all sorts of scrapes as a result of having her head up in the clouds, including sinking her best friend's father's dory while re-enacting Tennyson's "The Lady of Shallot." She mellows out with age, but still retains her wild imagination.
Isaac and Miria share a train of thought that has to be seen to be believed. For example, they once decided to steal a museum, building and all, for the sheer hell of it. Then they realized it was impossible... so they stole the door instead to stop people from entering. They plan a train robbery which "means going to the destination by train, then committing a robbery, then jumping on a train again to run away." Or the time Isaac decided to attempt to "steal gold directly from the earth rather than stealing it from the mafia". Through a process known to the sane as "mining", which he is convinced he invented. Did we mention that they thought bringing their friend a "little brother" as a surprise present was a fantastic idea? It also took them 70 years to realize that they were immortal. And they didn't actually figure it out. Their assumption was that they were reborn.
Graham Specter goes on a long rant about tedium, to the point of attacking his partner screaming "death to tedium!" before doing a 180 claiming that "tedium is good" and gives him time to "think about things." That's when he's not taking cars and people apart with a wrench bigger than him. He comes off as a crazier mix of both Ladd Russo and Issac/Miria.
From P. G. Wodehouse's Blandings Castle novels, Lord Emsworth. Emsworth is a doddering old man who cares about nothing more than his pig (which he christened the Empress of Blandings). Want to talk to Emsworth? Chances are he'll end up rambling about pigs, derail the conversation based on semantics, or just plain space out and not listen to you at all. Even if you're lucky enough to have a lucid conversation with him, ten minutes later he'll have forgotten about it (and quite possibly you) anyway.
The Butcher Boy: Francie is quite mischievous and delusional and unaware of the world around him.
Despite his perception in popular culture, Holden Caulfield is more Cloudcuckoolander than Emo Teen.
Then there's Seymour Glass: who (must) at least visit Cloudcuckooland...think about it - in "A Perfect Day for Bananafish" — his rant against the woman unfortunate enough to be on the same elevator: "If you want to look at my feet, say so. But don't be a God-damned sneak about it." Usually, though, he's too busy embodying human kindness as his family's own personal reincarnation of the Buddha (and after his suicide, more so).
In Kurt Vonnegut's Cat's Cradle, fictional Nobel laureate Felix Hoenikker, "father of the atomic bomb", was so easily distracted that, at one time, he completely abandoned the development of the atomic bomb to study the skeleton of turtles... his daughter suggested his desperate colleagues to simply remove anything turtle-related from his laboratory, and he'd forget about his fascination with them completely (they did, he did).
The Cat Who... Series: Elizabeth Hart sort of appears this way to the natives of Moose County. She's very intelligent, and rather down-to-earth despite her wealthy background, but she's got very different interests than most of the other characters.
In the Clémentine books, Clementine's friend Waylon believes that he has superpowers and also before eating anything conducts a pretend battle between his food items. A lot of this is toned down in the Sequel Series starring him.
Odiana of the Codex Alera series lives somewhere in the hinterlands between Cloudcuckoolander, The Ophelia, and Ax-Crazy. Not entirely unexpected, since she's an incredibly powerful empath with a past that could have driven even a normal person crazy.
Lawrence Pritchard Waterhouse, in Neal Stephenson's Cryptonomicon. He fails to realize that the barren place in New Jersey, full of pine trees, is in fact the Pine Barrens of New Jersey (that he's come to see) until it's pointed out to him. In a wondrously hallucinatory sequence set in those very Pine Barrens, he sees "the world's globe, not the globe fleshed with continents and oceans but only its skeleton: a burst of meridians, curving backwards to cage an inner dome of orange flame" surrounded with "webs of cable and harnesses of electrical wiring ... vast, ramified snarls of ropes and piano-wires, cables and wires." Only when he reports this to his friends the next day as a dream of a burning zeppelin do we fully realize that Waterhouse witnessed the destruction of the Hindenberg.
Dark Future: Commander Fonvielle in Comeback Tour, who regards the Josephites who've drained and reactivated the flooded and derelict Cape Canveral, as new NASA staff and Roger Duroc as the new President of the United States, while being otherwise entirely competent and connected to reality. Well, apart from a tendency to drool and eat his beard. He's also a literal Space Cadet.
Robert Marsh from Darkness Visible, who was driven mad by the influence of Unreality. The same fate befalls about a third of London's population before the book is done. Not that being insane stops Robbie from contributing to the plot...
Silent Angel from Decomposing Angel not only lives up to her name, but seems completely inactive and anti-social. Her spaced out and aimless drive around El Paso with Jonas shows us this. Her death has very little impact on her as a character.
Fregley of Diary of a Wimpy Kid. With the things he says to people ("I bet I can fit your whole foot in my mouth!" and "Wanna hear about my hygiene issues?"), the things he does (play in ball pits, show people his secret freckle, chase people with his boogers) and the fact that anything with sugar exaggerates all of these things, he makes some of the examples of this trope look normal.
The Bursar of Unseen University is something of a Cloud Cuckoolander. Since the overbearing Mustrum Ridcully took office as Archancellor of Unseen University and the various weird things that happened since then (including the movies-influenced invasion of Things from the Dungeon Dimension in Moving Pictures and the incident with Windle Poons becoming a zombie in Reaper Man), the Bursar's nerves have been worn threadbare, and given him a tendency to do and say odd things under pressure. Thankfully, his skill with numbers remains no matter how detached from reality he gets, and with a steady diet of dried frog pills, he consistently hallucinates that he is sane (just like everyone else...) and is able to function reasonably well. Though he still sometimes thinks he can fly, and him being a wizard, gravity isn't about to say otherwise.
"The Bursar was, as he would probably be the first to admit, not the most mentally stable of people. He would probably be the first to admit that he was a tea-strainer."
Discworld magic-users, as a rule, seem to cultivate a touch of Cloudcuckoolander-ness. One of the minor wizard characters at Unseen University has an office where the furnishings are entirely constructed of piled-up books, while a young witch-in-training from the Tiffany Aching series pins her hair back in a bun with a knife and fork. Apparently, too much power tends to drive witches insane (think of Black Aliss), so some witches try to channel their madness into a harmless form: "All witches are odd. It's best to get your oddness sorted out early on."
Carrot Ironfounderson, with his unshakable conviction that people are good at heart, is frequently thought to be one of these by other characters. They'd be absolutely right about that, if he didn't make it work. From about The Fifth Elephant he stops.
Leonard da Quirm, who designs war machines but believes that no ruler in their right mind would have their army use such horrible weapons. The bad news is, Havelock Vetinari is the only ruler in his right mind on the Sto Plains by these standards, realizing that war and empire-building are more trouble than they're worth; the good news is, Vetinari has Leonard safely locked away and working for him.
Moist von Lipwig is prone to employing these, including Stanley the pin collector, who was raised by peas. Not on, by. Also Owlswick Jenkins, an even more off-kilter Genius Ditz forger who makes copies better than the real thing. For that matter, Moist has some moments like this himself, although it's mostly a result of him living on the edge.
Dragon Bones: Ward's mother moved to Cloud Cuckooland eventually, to escape her husband's abuse. She did it deliberately to some extent, by ingesting herbs that affect the brain, but seems to be a natural Cloud Cuckoolander when the story starts - she never is quite there, and "only hears what she wants to hear." Ward followed her example and faked brain damage after a particularly violent beating from his father that made him unable to talk for some time. This, naturally, comes back to bite him when his father dies and he is deemed too stupid to inherit the castle and surrounding land.
By Codex Alera's same author, The Dresden Files: Harry Dresden has his spacey moments, especially when he's concussed, drugged, and/or in pain.
An especially egregious example in Cold Days, when he muses to himself on the 'swing a cat' saying. He then turns to Thomas and asks out loud where that expression came from, without explaining what expression he's referring to.
Don't forget: "DON'T MESS WITH A WIZARD WHILE HE'S WIZARDING! NOW GO GET ME A STUFFED ANIMAL!"
He comes off much, much more of one to those who are Locked Out of the Loop of the supernatural world, what with the whole claiming-to-be-a-wizard thing and all.
Izaya Orihara of Durarara!!. For example, he once came across three girls attempting to bully a fourth. His response to this situation is to rant incoherently at them for a few seconds before announcing that while he does not hit girls, he does rather enjoy stomping on their cellphones. He then proceeds to steal the lead girl's cellphone and stomp on it while laughing maniacally for a few second before stating that stomping on cellphones is extremely boring, and is no longer his hobby. At this point, the lead girl sics her boyfriend on him, prompting Izaya to pull out his razor blade and shave the man's head, though considering his status as a Troll, the clouldcuckoolander-ish behaviour was most likely deliberately invoked.
And Slon beats them all with this quote. "I'm not moving an inch until I've solved the mystery of the male nipples! This is my war!!"
In Alison McGhee's Falling Boy, everyone is a Cloudcuckoolander to some extent or another. With the Only Sane Man being a 16-year-old going through a major life crisis, the book consistently refers to "(character name) World."
Gates is a more disturbing example. Most of the things he says don't really make sense, and the people who employ him have a hard time understanding what in the world he's talking about. In fact, the last thing he does when Sousuke obliterates his AS (and kills him) is to play with his hair and say, "Maybe I cut it too short?"
That was a call-back to a comment several episodes earlier—when his AS shrugs off an attack by the enemy he declares, mockingly "That might have hurt me, if my sideburns had been shorter!" But Gates really is disturbed — he watches a nature film on squirrels while naked for recreation in one episode. It started out with footage of kittens, and while he was on the phone with one of his subordinates he was furiously tearing tissues out of a tissue box.
Sousuke: "Chidori seems to be bothered by something. Either that or she's been abusing drugs." Kyoko: "Er... I don't know about that..."
Mao references this. When Kaname commented that she thought everyone in Mithril had the same personality and attitude as Sousuke, Mao replied: "Ha ha ha... that kid's... a little special." And other times, she and Kurz reference how Sousuke isn't quite all there. Though Sousuke is one of the few, if not only Mithril member who was a Child Soldier. Sousuke's been fighting in wars since he was eight (and before that, he was being trained as an assassin by the KGB), whereas most of his fellow mercenaries started out when they were already responsible adults; with that kind of upbringing, he probably simply doesn't know how to respond to anything without breaking out some serious weaponry. Makes it a lot less funny when you realize his behavior stems from the fact that he simply can't believe that there are places on Earth where people are not always trying to kill each other. And we have the Student Council President who deems Sousuke's actions... appropriate. No wonder they share mutual respect.
Marianne Engel from The Gargoyle by Andrew Davis mixes this with The Ophelia. Even if her stories about her and the narrator's past life are true and not delusional, she still has a lot of quirks (including talking to herself in Latin, etc.)
Leelee in The Genesis of Jenny Everywhere is a borderline case; not terribly bright or imaginative, but lives her life with no apparent sense of routine or even logic- one day turning up to school early because the lesson first period might have sounded interesting, the next bunking off and riding around random places, such as to the local park to scare the ducks (apparently her favourite pastime when not hanging round with Jenny). Lampshaded by the resident Alpha Bitch who is Jenny's main antagonist at school.
Terrible how you two have to put up with an erratic typical fluffy-headed woman, but answer me anyway.
Greystone Valley includes a wizard who can't read his spellbook, a warrior who can't stand the sight of blood, and a mouse-sized dragon. Somehow, they all manage to come through when they're needed most, though.
Faye from The Grimnoir Chronicles is a teleporting Okie girl who thinks several times faster than everyone else and is really good at killing people. She tends to sort everyone she meets into one of three categories: 'Friends,' 'Stupid,' and 'Needs to Die.'
Luna "Loony" Lovegood rules this trope, as well as The Cuckoolander Was Right. She belongs to House Ravenclaw, which values intelligence and creativity, and she believes so many oddball things - but has a surprisingly profound emotional intelligence. After the final battle with Voldemort, she becomes a wizarding naturalist and discovers many creatures nobody else thought existed. This being Harry Potter, she never does manage to find a Crumple-Horned Snorkack. C'est la vie.
Deathly Hallows introduces Luna's father, Xenophilius. In his first scene (at Bill and Fleur's wedding), he makes it clear where Luna got her eccentricities from. Even before that, Luna mentioned that he edited The Quibbler, known for writing about bizarre conspiracy theories.
Professor Trelawney, the Divination professor, dramatically and inaccurately predicts the death of one of her students each year. She also refuses to join a table if thirteen people are seated. She's convinced that the first to rise will be the next to die. She does accurately predict that "one of our number will leave us forever" ... which turns out to be Hermione dropping the class.
Dumbledore comes across as incredibly strange in his thought patterns and interests. During the Welcoming Feast in Harry's first year, his opening remarks are "Nitwit. Oddment. Blubber. Tweak." When Harry hesitantly asks a fellow student about the Headmaster, Percy confirms that he's brilliant, but a little mad. And according to the man himself, when he looks into the Mirror of Erised, which shows you your heart's deepest desire, he sees himself holding warm woollen socks. But the final book very heavily implies that he saw the same thing as Harry, the family he lost.
The titular character, who rants about dumping all her previous boyfriends because they weren't aliens, time travelers, or espers, seems to fit this trope at first... until her criteria turn out to be less farfetched than they seem...But, even without the reality warping powers, she still does some pretty odd things — believing that wearing a Playboy Bunny suit at school to advertise her new club is a-okay, among other things. Ultimately downplayed because, despite her outward wackiness, Itsuki Koizumi points out that Haruhi is a rational person who ultimately does not believe in the supernatural.
Kuyou Suou, though this is largely due to her Blue-and-Orange Morality. She is an interface for the Sky Canopy Domain, an alien entity with thought processes fundamentally different from those of humans. The SCD is just beginning to learn how to communicate with humans resulting in strange behavior and statements from Kuyou.
Also downplayed for Yuki. Kyon thinks she must be this at first when she dumps a lengthy dissertation on him explaining how she's a fragment of an alien superbrain and Haruhi is some kind of human data bomb; but, of course, it's all true. But she also does some pretty bizarre things later on, like when Kyon tells her to "stop" and she freezes in place until he realizes he has to tell her she can move again.
In Moira J. Moore's Hero series, being a Cloudcuckoolander is the first symptom children show when they will grow up to be weather-workers called Sources (and be required to have a soulmate The Stoic who can translate for them).
Ford Prefect seems like one of these on Earth, staring into the skies looking for green flying saucers and laughing at astrophysicists, and telling everyone that a particular Thursday is The End of the World as We Know It. When they leave Earth and Arthur finds out he's an alien, these habits start to make sense. But Ford continues to be a Cloud Cuckoolander with his main goal in life being to get drunk and dance with girls, and trying to get out of saving the universe by claiming he had a doctor's note.
Zarniwoop: And they ask you to make decision for them? About people's lives, about worlds, about economies, about wars, about everything going on out there in the Universe? The Ruler of the Universe: Out where? Zarniwoop: Out there! The Ruler of the Universe: How can you tell there's anything out there? The door's closed.
To the Ruler, everyone else (if they exist) is the Cloudcuckoolanders. They persist in believing things that they have no immediate, direct evidence for — like what's on the other side of that closed door — and insist that things are as they say they are without even considering the possibility that they could be otherwise. And then they get angry about it.
In the Jorge Luis Borges short story "The House of Asterion", the freaking Minotaur is made into one. This is somewhat justified as he has spent much of his life alone in the Labyrinth.
In Garcia Lorca's The House Of Bernarda Alba, the grandmother appears completely crazy and delusional; she takes out the jewelry and says she wants to get married, then appears cradling a lamb as if it is her baby. Yet she occasionally says what all the other characters should be thinking, and is the first to voice her protest against Bernarda's tyranny.
Apparently how Wiress's traumatization from being in The Hunger Games has manifested. She rarely speaks, and when she does she tends to drop of mid-sentence, she has trouble expressing her thoughts, and she has a habit of "randomly" reciting old nursery rhymes and seemingly random words or phrases. But she is very smart and knows what she's talking about, if you can figure out her train of thought.
In the In Death series, Dennis Mira, Dr. Mira's husband. Incredibly sweet and empathetic but rather spacey. Eve finds him oddly charming.
Angela of the Inheritance Cycle comes out with random non sequiturs frequently. In her spare time, she tries to prove that toads don't exist. Even when she's holding one. This may lead to a Mind Screw, she and the main characters get into a discussion about how the toad she's holding is actually a frog...excuse me, my brain hurts...
Though, there is the possibility that she is Obfuscating Insanity, as there are a few times where she drops the weirdness. Namely, when she finds out Eragon met her mentor, and when she crosses enemy lines to poison the invading troops.
Deconstructed in Ironman with Hudgie. His inane ramblings are treated as a severe threat to his own well being, and it's heavily implied that he is incapable of rational thought anymore. Oh and the reason he's like this is due to the horrific emotional abuse and flatout torture his psychotic father subjected him to his entire life.
Rui Takamiya from The Key of Yliaster is kind of like this. She admits that she is insane, and does things like asking people if they are gummy bears, for crying out loud. She also apparently believes that gummy bears have souls and that they can somehow reincarnate.
The Kingkiller Chronicle: The nature of the Doublethink required to work this universe's particular brand of magic can be rough on one's sanity, so this series has more than its fair share of this trope:
Master Elodin. One example of his cloudcuckoolander tendencies would be the time he told Kvothe that he had 'lost' the key to a door, framing it as a test, and then when Kvothe had picked the lock, proceeded to empty the room's wardrobe into the fireplace before revealing that they were actually in the chambers of Master Hemme. Also, his teaching techniques are... questionable at best; see the time he assigned his students a twenty-title reading list, all the while emphasizing that he had no idea where in the Archives the books could be found, or if they were even there at allnote Although Kvothe manages to find all but one; they seemed to have no relation to each other, much less to Elodin's teachings. The next class, when everyone arrived ready to discuss what they had read, he simply didn't show up. He also has a penchant for going barefoot.
Aurinote Not her real name, which she refuses to tell Kvothe, a former student who now lives in a network of disused chambers, tunnels and sewers beneath the University, which she refers to as 'the Underthing'. The only people she seems able to talk to are Elodin and Kvothe, and she tends to bring them generally mundane gifts to which she ascribes mystical-sounding but ultimately meaningless secrets. She shares Elodin's aversion to shoes.
'Puppet,' a former student like Aurinote His real name also isn't Puppet, lives in the Archives, has a strange obsession with puppetry, has seemingly committed the text and location of most items in the Archives to memorynote Keeping in mind that the Archives are so expansive that no one has successfully managed to finish organizing them in centuries, and, perhaps most oddly, answers his door by impersonating an ancient hero, and if he doesn't feel he's gotten the impression right, he'll slam the door on you and request loudly that you knock again so he can make another try.
Knaves On Waves gives us Magwa, an oddly relaxed warrior who often spouts nonsensical wisdom, believes in bizarre omens, and refuses to ever put down his axe. He's the oddest member of his crew, which is definitely saying something.
Goss from Kraken is an interesting case. He's either this trope or a subversion, depending on your point of view. He does understand what's going on, but has a tendency to speak in such a bizarre vernacular (speaking to people as if they were school friends, or magical princesses, or something equally as strange), frequently chides his silent partner Subby for being a chatterbox, and has a tendency to ignore whatever others say that doesn't fit into his strange little world. Given that he's an Ax-CrazyPsychofor Hire, his bizarre way of behaving is even more terrifying.
In The Last Unicorn, the butterfly sings songs, recites poetry, quotes a warning from a matchbox at one point, and occasionally says something useful. It's at least implied, if not stated outright, that verbatim parroting what he's heard others say before is actually the only way any butterfly can talk at all. He seems to understand what the unicorn is after well enough, though.
The Harpell family of wizards in The Legend of Drizzt books. List of "experiments" include trying to cross a horse with a frog; accidentally turning themselves into dogs; physically relocating their brains to their buttocks; separating their eyes from the rest of the body and getting stuck that way; believing double initials to be important omens, etc., etc. All the while beaming happily. The really weird part is that their experiments tend to have successful side effects — the one who turned himself into a dog, once turned back, ended up a werewolf; the one who tried to cross a frog and a horse succeeded (he dubbed the result "Puddlejumper"); and the brain-switching was actually with purpose, as it was done to fight against brain-eating monsters. This may mean the family hinges on being a clan of The Fool.
As for Harkle Harpell's eyes being teleported away from his body, he actually had an excuse that time: it happened during the Time of Troubles, during which everybody's magic spells went wrong somehow. Harkle tried to teleport his entire body before he knew the situation, the result being that he was able to see his intended destination (since his disembodied eyes were there) and talk to the people there, but his body remained behind. He was blind to his immediate surrounding until his colleagues were able to help him make the trip overland and reinsert the eyes in their sockets.
Brandon stands out in The Leonard Regime due to his unusual behavior and overall obliviousness.
Discussed in Lord Chesterfield's Letters to His Son. He wasn't too fond of this trope: "Sir Isaac Newton, Mr. Locke, and (it may be) five or six more, since the creation of the world, may have had a right to absence, from that intense thought which the things they were investigating required." (letter I)
Shane Fergussen calls Victor several terms usually associated with royalty when he orders a grape soda, including shouting "A grape soda for a prince of royal blood!" into the street. He's also friends with the Chicken Man and they watch the lizards together.
The lizards are only shown to have three distinct names note Reynold, Raymond, and Helena but always know who's being addressed, and invented their own form of television long before humans did that's watched with one's eyes closed. The lizards revere chickens and an egg that's the focus of a prophecy, and have a culture-wide appreciation of Walter Cronkite.
Morganville Vampires series: Myrnin (a vampire mad scientist with bunny slippers) and Miranda (a psychic ghost child).
Mr. Men: Roger Hargreaves seems to be fond of this type of character.
Mr. Silly puts marmalade in his coffee, lives in half a house, eats the shell of an egg and finds the idea of a hen who doesn't wear boots and carry an umbrella, a pig who doesn't wear trousers and a bowler hat and a worm who doesn't wear a top hat, monocle and an old school tie silly. The fact that he lives in a place known as Nonsenseland certainly doesn't help.
Mr. Muddle is so named because everything he does ends up in a hopeless muddle. He wanted to live in the countryside but got muddled and built his house by the seaside instead, and when he tries to make a roast dinner of turkey, potatoes, peas, and gravy, he puts the turkey in the cupboard to cook and the potatoes in the fridge to boil, then peels the peas and tries to slice the gravy.
Little Miss Scatterbrain is constantly confusing the names of the other Mr. Men and Little Misses, and when she goes into town to buy sausages, she walks into a bank instead and asks for two pounds (of sausages), then wonders what the two notes the bank teller passes her are in aid of.note
Mr. Rush is a guy who rushes around all day going... nowhere.
Mr. Nonsense, as befits his name, has a truly nonsensical way of looking at the world. He sleeps in a rowboat (he found a motorboat too uncomfortable) and eats oatmeal on toast for breakfast (he tried oatmeal sandwiches once but didn't like them).
Mr. Topsy-Turvy is the worst. He walks backwards, reads books upside-down (and starts from the last page), has a crazy-looking house, and talks in sentences with the words mixed up. Even worse, this behavior is catching; when he visited a city, the folks there started acting like him.
Mr. Wrong wears a flower pot for a hat, he wears one shoe that's black and one shoe that's brown, calls a worm a dog instead of a worm, calls a postman a doctor instead of a postman and calls his elderly neighbor Mr. Twinkle instead of Mrs. Twinkle.
Little Miss Dotty is so named for her dotty ideas, like covering her house in dots, for instance.
If left to her own devices, young noblewoman Katarina will do insane things like plow fields and create toy snakes to attempt to terrify her fiancee because she's positive that one day he may try to kill her.
Oblomov. It's not really funny: Instead of caring for the village he owns, he spends years of dreaming up improvements and does effectively nothing.
Dean Moriarty in On the Road. Kerouac's fictionalized version of Neal Cassidy drives 100 mph naked through the midwest in a borrowed car without a second (or first) thought. This not extreme behavior for this guy.
Dwight from the Origami Yoda series is a Cloudcuckoolander. He lies down in random places, and once thought that there were squirrels inside a locker he needed to open note He thought that lockers opened from the inside, so he asked the squirrels to open it for him. .
A great deal of the plot of Pippi Longstocking revolves around Pippi living in Cloudcuckooland while the adults and others don't.
Pippi is first encountered walking backwards so that she doesn't have to make the effort to turn around to go back where she came from. (Though quite possibly, she was trying to catch the other kids' attention.)
Her reaction to an ad asking "Are you suffering from freckles?" is to march inside the store and answer "No, I'm not suffering." (She has loads of freckles but likes them.)
The Pirate Captain from Gideon Defoe's The Pirates! series. In one book he is told to concentrate and stay focused. Somehow he turns this into a ten-page daydream about a world made out of mint, where a lazy king tricks people into doing his yard work.
Awareness is like consciousness. Soul is like spirit. But soft is not like hard and weak is not like strong. A mechanic can be both soft and hard, a stewardess can be both weak and strong. This is called philosophy or a world-view.
Bat Jarvis, from "Psmith, Jouralist", the gangster who's prone to ask you if you've ever had a cat with different-color eyes.
Sacksby Senior from Cocktail Time. He has a habit of misinterpreting everything that is said to him, and he also refers to his acquaintance Lord Ickenham as 'Scriventhorpe', for no discernible reason. Out of Wodehouse's cloudcuckoolander characters, he is arguably the most divorced from reality:
Sacksby: Ah, Scriventhorpe ... you seen Flannery lately?
I'm not absolutely certain of my facts, but I rather fancy it's Shakespeare—or, if not, it's some equally brainy lad—who says that it's always just when a chappie is feeling particularly top-hole, and more than usually braced with things in general that Fate sneaks up behind him with a bit of lead piping.
Who is totally upstaged by Madeline Bassett, a girl who he has the misfortune of being occasionally engaged to, and who comes out with bizarre statements about the stars being "God's daisy chain" and such.
In fact, let's just go the whole nine yards and say that everyP. G. Wodehouse character probably has at least a smidge of this. Yes, even you, Jeeves.
Assol from The Scarlet Sails, who believes in fairy tales and a prince who will come for her on a ship with scarlet sails.
An example that helped define this trope is James Thurber's 1939 short story "The Secret Life of Walter Mitty." The titular hero is a mild, unassuming man who's prone to spinning off into elaborate heroic fantasies at the slightest real-life suggestion.
In Patricia C. Wrede's The Seven Towers, the sorceress Amberglas is somewhere between this and Obfuscating Stupidity; her constant rambling digressions seem to be genuine, but she's much sharper (and more powerful) than she gives the impression of being, and frequently she has important things to say if you can sort them out from the nonsense.
Jeanne from Charles Baxter's Shadow Play. She invents new words like "zarklike", "corilineal" and "nutomberized", talks to herself, believes she's drifting on an ocean liner, speaks in metaphors, sees angels and so on and so forth. At the same time, she's often wise and loving. She actually understands she's crazy, but seems to choose madness over sanity and prefer living in her own universe. As her son Wyatt said about her, "you couldn't be insane by choice, but she was."
Eliza in Someone Else's War. Her chipper nuttiness is a breath of fresh air, considering that the rest of the novel is one relentless punch to the gut after another. The same novel also gives us Abdel, a quirky little weirdo who arbitrarily decides that he is psychic.
Stargirl in Stargirl by Jerry Spinelli. Doesn't wear makeup and carries a ukulele around school and serenades strangers in the canteen with music from it on their birthdays. Also decorates her desk each period with a tablecloth and flowers.
An interesting variation occurs in Summer of Eternity. The mother of one of the characters learns that her husband helped commit a murder and has been arrested. She has a complete breakdown, as a result. For the rest of the book, she is in a cheerful mood and is off in her own little world, believing that her husband is off at work rather than at prison. The trope is played straight, but due to the context in which it is played, it comes across as heartbreaking rather than funny.
Patty, the 12-year-old protagonist of Summer of My German Soldier, is virtually friendless and suffers abuse at the hands of her parents. She often escapes into daydreams as a coping mechanism.
Minori "Minorin" Kushieda of Toradora! probably counts. In one of her very first scenes she's staring up at the sky and suddenly remarks "The sun is dry...". Her Cloudcuckoolander nature continues from there, but ends abruptly once Taiga's father reappears.
Abel Nightroad of Trinity Blood has elements of this, particularily in the manga. It's espicially more prevalent in the earlier chapters, when he's traveling to the Vatican with heroine Esther and Terminator 2-esque Tres; at one point, he opens a window in a moving train because he wants to feel the breeze. A few chapters later, while on a cruise ship, he's immediately suspicious of how nice it is and insists that something bad will happen, citing the events of fiction such as Treasure Island and Titanic, which Esther immediately Lampshades. In this case, he's right, which may qualifies him as being somewhat Genre Savvy.
In The Trolls there is a woman nicknamed "Mad Maud" from Aunt Sally's stories who lived in a house filled with stuffed animals she supposedly shot herself and routinely goes cougar hunting in the woods surrounding her house. Said cougars were actually squirrels, and her aim is far from accurate.
Dr. Roger Burrows, the wanna-be Adventure Archaeologist of the Tunnels series. He tends to get so caught up in his admiration of ancient artifacts that he neglects trivial matters such as the fact he ran out of food three days ago and is surrounded by large carnivores. He does however have enough of The Fool archetype to survive most dangers by virtue of simply not noticing them.
Wendy from John C. Wright's War of the Dreaming is similar to Eilonwy—a Genki Girl who believes she forgot how to fly and runs naked in the woods trying to remember, gets sidetracked during a conversation to hunt for elves, and isn't at all surprised when a armored knight-errant climbs through the window in her hospital room.
Subverted in Watashitachi No Tamura Kun. Matsuzawa doesn't actually believe what she says, her belief that she is an alien from the moon is an admitted coping mechanism for the deaths of her family members, as she believes she will be able to meet up with them on the moon in the afterlife.
Marcus from When You Reach Me is this on occasion. He doesn't always notice people around him or where he is.
Just about anyone in Winnie the Pooh besides Eeyore. Kanga's a bit more stable, too, if a little overprotective.
The Mnomo in Wise Phuul are an entire race of these.
Shallan can come off as this when the scholarly side of her takes over, such as interrupting Adolin's boasts about his battles on the Shattered Plains to wonder how he poops in Shardplate.
The old man Lift meets in Edgedancer is spending his free time sitting on a bench, interrupting random people in the street and asking them which body parts they are, treating any answer as absolutely honest. He claims he's trying to form world's ultimate philosophy. With the reveal that he's actually a Hive Mind made up of dozens of insects specialized in functions of various body parts, this makes a bit more sense.
Let me put it this way, sir. If you ever meet an etherealist who does not seem odd, you will have ample reason for caution. An etherealist who speaks to things that are not there and cannot track the day of the week is par for the course. One who is perfectly well dressed, calmly spoken, and inviting you to tea? That is someone to be feared.
The Southern Reach Trilogy: Whitby was eccentric before his unauthorized trip into Area X with the director. What he saw there didn't help his state of mind one bit. He drifts in and out of focus, voicing cryptic suggestions, and Control remarks how Whitby's theories make sense only on the surface but descend into outlandish fantasies upon a closer look.
The Witches: An endearing example in the taxi driver near the end of the story, who sees the hero in mouse form in his grandmother's hand, and is not fazed at all that the mouse is her grandson.
Taxi driver: Blimey! What's that?
Grandmother: It's my grandson. Drive us to the station, please.
Taxi driver: I always liked mice. I used to keep 'undreds of 'em when I was a boy. Mice are the fastest breeders in the world, so if he's your grandson, you'll be having some great-grandsons soon.
Grandmother: (looking prim) Drive us to the station, please.