Let's start off with the Crowner of Crownersnote Possibly equaled, unlikely to be surpassed. so far as the Vorkosigan Saga is concerned: The Shopping Trip from Barrayar.
Cordelia, Droushnakovi, and Bothari shanghai Koudelka into helping them recover the Uterine Replicator containing Miles' fetus (which had been captured by enemy forces and will fail from lack of regular maintenance within a week) and Princess Kareen, explicitly against Aral's wishes.
After infiltrating the capital — which is solidly held by "Emperor" Vidal Vordarian — the group finds that the missing Alys and Padma Vorpatril are hiding near the not-so-safe-house they've picked. Cordelia runs an Indy Ploy to try to rescue them. It's only partially successful: Padma is killed in the crossfire, but Alys and baby Ivan are successfully exfiltrated from the capital by Kou.
Using Drou's knowledge of the Palace grounds from her training as Princess Kareen and Prince/Emperor Gregor's bodyguard, the remaining three successfully enter the residential wing and locate the Replicator. Cordelia Turns Kareen to their side...with a shoe. Unfortunately, Kareen's reaction is a bit extreme, and she is killed in the scuffle; most of the wing is set ablaze. Faced with the problem of leaving the palace grounds with a very uncooperative hostage (Vidal Vordarian), Cordelia has Bothari take more direct measures to deal with it. As an afterthought, she decides to put a souvenir of the expedition in a plastic shopping bag she picked up from the residence.
Upon returning to Aral's headquarters (with Replicator and Vordarian) the classic exchange occurs. (This also counts as CMoF material to many.)
Piotr: Good God, woman! Where have you been?
Cordelia(Holding up the plastic bag): Shopping. Want to see what I bought?
Vordarian's head is rolled out on the conference table to a mixture of shock, horror, and grim amusement.
Aral: [deadpan] But of course. Every Vor lady goes to the capital to shop.
Cordelia: I paid too much for it.
Aral: That, too, is traditional.
Aral then asks all the men to leave for a moment.
Aral: Gentlemen. If you will be pleased to excuse yourselves for a few minutes. I wish to be alone with my wife.
Anonymous whisperer: Brave man.
This is followed by a comment to some of Vordarian's men in the room.
Cordelia: Officers. I recommend that when this conference resumes, you surrender unconditionally upon Lord Vorkosigan's mercy. He may still have somenote Unspoken but nonetheless clearly heard are the words, I certainly don't. I'm tired of your stupid war. End it.
The War of Vordarian's Pretendership comes to a rapid conclusion, and a Barrayaran legend is born.
From The Vor Game, Miles' scheme for rescuing Gregor from Cavilo, culminating with the Shoot the Hostage gambit. Bonus points for Gregor picking up the ball and completing his own rescue by seducing his seducer, convincing her she can marry him and become Empress, and then leads her into scrapping her own plans before Miles gets him to safety. This is the time where Gregor gets to shine, and his gloating to Cavilo says it all:
"Commander Cavilo, both my parents died violently in political intrigue before I was six years old. A fact you might have researched. Did you think you were dealing with an amateur?"
Ekaterin scores a nice one toward the end of Komarr. Her Adrenaline Makeover prods her into creating a mess that even Miles would be proud to call his own. (Start with a standard Sick Old Lady ploy to distract your guard. Run for a sealed control booth in the ensuing confusion. Use the remote control for a float pallet on which a Nefarious Device is loaded to first raise it to a height of 4 meters, invert it, then shut off the anti-grav. Bounce the rubble on the floor a few times just to make sure. Then use the comconsole in the booth call for help, as it was too late for any errors on ImpSec's part to screw up the important matter.)
The same couch that Kou and Drou used to umm... consummate their relationship in Barrayar
It was just as awesome when she got Kou and Drou together by doing pretty much the same thing in Barrayar. While on a covert mission deep in enemy territory, no less.
In The Vor Game, Miles not only brags to Cavilo that he got paid three times over, including from the planetary government she betrayed, but foils her last attempt to annoy him (by wearing perfume he has a severe allergy to) by producing nose plugs.
A lovely Ironic Echo, too, as Cavilo's original plans were supposed to culminate in her getting paid three times over.
Cavilo has her own Crowning Moment when she kills Metzov with his own nerve disruptor, after he'd raped her: "Stanis, darling. 'Spread your legs for me, you bitch, or I'll blow your brains out'."
Miles and Gregor messing with Cavilo. The first phase: Miles portrays himself to Cavilo as an Evil Chancellor, ready to betray Gregor, Aral, and the entire Council of Counts. The second phase: Gregor (who's been isolated from everyone except Cavilo) is shown evidence of Miles' "betrayal", and segues into a portrayal of Miles as an unstable, hilariously incompetent schemer with Chronic Backstabbing Disorder, generally harmless so long as he's properly medicated. (Elena, who's known both of them since she was born, is literally rolling on the floor at this point, biting her sleeve to stifle the laughter.) The third phase:
Miles: Deactivate your weapons and freeze, or I'll blow Gregor to atoms!
Gregor: His meds must be further off dose than I thought. No, watch—he's bluffing. I'll prove it.
Gregor then proceeds to walk right up to the (deactivated; although Gregor didn't know that, he suspected it) muzzles of the large energy weapons pointed at him, so mesmerizing those watching that they don't notice he's crossed the hangar blast door threshhold—until Miles bangs down the blast doors. Only then does Cavilo realize how completely Gregor and Miles, without any chance to coordinate, have, in concert, tricked her into doing just what they'd wanted.
Ekaterin's marriage proposal. In front of the entire Council of Counts in session. Also a Crowning Moment of Funny. "Twit." That scene was arguably a CMOA for several other characters as well. Ivan, Dono, and Count Vorhalas all had a hand in the awesome there.
Mirror Dance. Mark, when he realizes he can deal with Ryoval: "You see me, Baron. But I see you, too."
Mark's hands down CMOA are his Pre-Mortem One-Liner to Ryoval: "I am too a Vorkosigan. The one who was trained as a deep-penetration mole and assassin. It really pisses me off when people underestimate me, y'know?"
In Brothers in Arms: Duv Galeni, who is an ImpSec captain and therefore trained in combat, hand-to-hand or otherwise, but not to the standards of someone expected to need it frequently, has just had a Very Bad Week involving some epic Daddy Issues. He's chatting with his Cetagandan counterpart, playing I-know-you-know-I-know, when he's surprised and stunned by an actual commando, a Cetagandan Century-captain. He was only Mostly Stunned, though, and when he's started to recover a bit, he takes on both officers in a bout of Percussive Therapy that leaves deep skull-shaped dents in the fender of a nearby car. This was all offscreen, so we get it in bits and flashes from Miles's increasingly impressed/disturbed perspective.
Aral has a very low-key one in Barrayar when confronting his father after Piotr tries to have Miles' fetus dumped. As Cordelia mentally remarks, One day only: The Irresistible Force Meets the Immovable Object. Tickets, five marks.
Claire gets one in Falling Free when she breaks her slave mentality and overpowers a tech trying to sterilize her.
She grinned in wild exhilaration, brought his arms in, out again at will. I'm stronger! I'm stronger! I'm stronger than him and I never even knew it. . . .
"The Assault on Cockroach Central" in Memory shows Miles' Guile Hero talents in all their glory. He's not just a master of the Indy Ploy; given time to set up his Batman Gambit, he can plot with the best of them, doing an admirable job of covering all the bases and setting up his supporting cast to supply needed lines at the proper time. (Granted, Bujold follows the Unspoken Plan Guarantee trope by not letting the reader in on the scheme in advance, helping to ensure it goes off without a hitch...)
In Cryoburn, Consul Vorlynkin holding off the ninjas arsonists attempting to torch a cryo-clinic, saving hundreds (or even thousands) of lives in the process. Single-handedly. With a crowbar. Which he took away from them; he was empty-handed at the start of the fight.
Cordelia's Shopping Trip was preceded by a long string of awesome moments.
After her shrink has a Critical Psychoanalysis Failure, Cordelia is about to be forcibly taken for "treatment." Two of her superior officers and a mook are there to make sure she goes. Cordelia holds the shrink's head in a fish tank to find out where the others are, and then faultlesslyIndyPloys her way to safety.
Infiltrating the Anti-Mutiny on the General Vorkraft and stunning every man there, before escaping back to her own ship. This is when the other best idea was a head-on assault into battlefield-grade weaponry through a choke point deliberately designed as a defensive killing ground.
"Borders of Infinity" is one big CMOA for Miles. Drop a single man in a prisoner camp. He's a dwarf with brittle bones. He has nothing, not even clothes on. What do you think will happen ? He liberates the whole camp, of course.
In Shards of Honor, Vorkosigan's first truly badass scene where he gives the guy a gun and turns his back to him.
I told him I couldn't work with a man who made my shoulder blades itch, and this was the last chance I was going to give him for instant promotion.
Even better, Aral admits that he never tried it before, and the only reason he tried it was that he was physically exhausted and didn't care if he got shot or not.
The Zero-G Quaddie ballet in Diplomatic Immunity. After that slice of awesome, Miles thinks to himself that nobody could see that and imagine that the Quaddies were some kind of cripples or mutants.
Nikki Vorsoisson in A Civil Campaign. A paternal relation is trying to take custody of Nikki against his will - so he calls the emperor for help. I repeat he calls the freaking emperor!!
In addition, the emperor in question answers, summons all concerned to his closest office via Secret Police, and cuts out of a parliamentary hearing to straighten said relation out in person which makes it a CMOH.
Even better, Gregor tells young Nikki why and how his father died in ways that Nikki can understand, all the while protecting his father's reputation in his eyes. Ekaterin at first begins to protest, but realizes that Gregor was giving Nikki the softened version of his father's actions, which were completely self-interest and self-destructive.
If that weren't enough, Gregor is also dealing with an incident related to Tien's death that would have caused a civil war between Barrayar and Komarr, so it was a highly classified state secret. The way he worded it gave Nikki a stake in keeping it secret to preserve his father's rep, so Gregor killed two birds with one stone.
Falco: There is an unwritten rule among us, Richars; if you attempt any ploy on the far side of ethical, you'd damned well better be good enough at your game not to get caught. You're not good enough.
Just before that, Ivan gets his own CMOA in that he finally out-Miles Miles, and enjoys every second of it, savoring Miles' awe.
At the end of Diplomatic Immunity, Miles is called upon by the Star Creche to donate his genetic material. That's right, the superhuman haut ladies think that Miles is awesome enough to have his genes studied for possible inclusion in a future generation.
In Winterfair Gifts, Sergeant Taura is the first one to notice there's something fishy about Ekaterin's illness, and uses her own genetic modifications and Roic's help to suss out the source of it...which just so happens to be some doctored pearls that passed the gift screening, thus saving Ekaterin's life.
Captain Vorpatril's Alliance has Tej's grandmother, Moira, rediscovering the Cetagandan gene survey of Barrayar and then offering to sell it back to the Star Creche. Note that Moira is still somewhat pissed off about being culled from the haut genepool, even after a hundred plus years, besides her ghem husband and various other compatriots being screwed over by the Cetagandan Empire. So, when the buyer from the Star Creche is right in front of her, Moira vaporizes the brooch in which the gene survey is stored.
Ekaterin's motivational speech to Miles in Diplomatic Immunity
Ekaterin: If you die on me out here, I will not be grieved, I will be pissed. This is all very fine, love, but may I point out that you don't have time to indulge in angst right now. You're the man who used to rescue hostages for a living. You are not allowed to not get out of this one. So stop worrying about me and start paying attention to what you are doing. Are you listening to me, Miles Vorkosigan? Don't you dare die! I won't have it!
Miles: Yes dear.
Ivan, after putting up with his wife's family with superhuman patience, has - because of their greed and attempts to reclaim a Cetaganda treasure stash - ended up trapped with them in an underground chamber that is both running out of air and filling up with water. (Keep in mind that Ivan, thanks to a misadventure a few books back, is claustrophobic.) Then one of Tej's sisters manages to set herself on fire, thanks to some dodgy aged perfume. While everyone else is panicking, Ivan swiftly gets her to stop, drop and roll, and puts the fire out with a bin. Then, finally having had enough, he climbs up onto the bin and Tej realises that 'goodness, he could yell':
"Could you people stop trying to come up with novel ways to kill me for just one hour? Or maybe the rest of the night? I would so like that. Just the rest of the night. Just sit down. Just stop doing anything. Sit down and wait sensibly. Earth, water, air, fire - you're running out of elements, here!
This helps in finally gaining him the respect of his in-laws, since they actually start listening to what he has to say after that and taking him seriously.
Ekaterin, in Komarr, gets one by standing up to her abusive husband and telling him point blank that she's going to leave him, never losing her temper or showing fear even when he throws one of her prized plants over the balcony. Miles himself understands how brave this was, as he knows full well how dangerous it can be to challenge someone bigger and stronger than you.