Waif Fu



""Start with the part where Jayne gets knocked out by a 90-pound girl, 'cause... I don't think that's ever getting old.""

- Wash, Serenity

The tiny, hundred-pounds-when-soaking-wet Damsel in Distress is under attack. But wait! She just took down a man three times her size without breaking a sweat. Well, size isn't everything. If you know the right martial arts, then Muscles Are Meaningless.

Sometimes empowerment fuels Waif Fu, but Rule of Cool is the main source of power.

More realistic depictions of combat between a Waif Fu user and an opponent who depends on strength and size (see The Big Guy, Mighty Glacier, Boisterous Bruiser) can be quite exciting. Typically the practitioner of Waif Fu will be slapping around the attacker, doing all sorts of damage to him while he struggles to land a good hit on her. It looks like she might win. Then he finally lands a blow, and she goes flying.

It's useful for a narrative since the implication is that if she does get captured or pinned she won't be able to break free since she depends on her cool moves to win rather than simple strength. Theoretically this allows her to be made into a kidnap victim when the plot demands it without turning her into the Faux Action Girl. However, when handled badly she can end up there anyways.

A character dependent on Waif Fu is likely to be a Fragile Speedster. Sometimes Super Strength is added on, but it doesn't make a lot of sense then as to why she insists on using a combat style suited for a weaker person fighting a stronger opponent.

A subtrope of Pint-Sized Powerhouse. Often used by the Action Girl, Faux Action Girl, Hot Amazon, Little Miss Badass, and Lady of War. Very common among characters of the Mary Sue variety. Compare to the Cute Bruiser who uses a completely different style of combat and Vasquez Always Dies where the females who do look like they can wipe the floor with you never do.

Has nothing to do with MY WAIFU.

Anime and Manga

 * Sakura of Naruto learns it from Tsunade, who also breaks the ground with simple punches - Tsunade in her true form is actually a frail elderly woman with even less muscle size than Sakura. This Super Strength is apparently achieved by perfect chakra control.
 * Hinata also falls into this category in a way; her clan's specialty is the "Gentle Fist" technique, which rather than using crippling damage delivers a short, intense burst of energy to block a chakra point, preventing the use of ninja techniques (and potentially the use of limbs, or *organs*). In the anime, she's also shown the ability to improve the "near perfect defense" technique to a "truly perfect defense", and turns the Gentle Fist into something that would make Kenshiro start to shed Manly Tears. At least, she does this occasionally. Hinata would probably be stronger were it not for her absolutely crippling self-esteem issues, which are only sporadically overcome by following Naruto's example.
 * Yachiru Kusajishi of Bleach is able to carry her captain, Kenpachi Zaraki, without much trouble despite her being about 33 pounds (15 kg) whereas he weighs in at a Tyson-esque 237 pounds (108 kg).
 * Ururu, the little girl that helps out at Kisuke Urahara's shop, also deserves a mention here. When the arrancar first invade the real world, she snaps and starts kicking ass, much to everyone else's shock. She also showed off some of her skills back during Ichigo's Training from Hell.
 * Soi Fon is the captian of Squad 2. She's under 5-feet tall, fast as hell, and her zanpaktou is essentially a hornet's stinger.
 * Also Yoruichi, who is known as the "Goddess of Flash" and laid Yammy Rialgo out with no help at all. She also gets points for drilling into the ground not once, but twice.
 * Elizabeth Middleford from Black Butler.
 * Slender fifteen-year-old Kaoru Konoe of Gate Keepers has the ability to heft battle tanks and throw buses for hundreds of yards, thanks to her Gate powers.
 * Shinobu in Urusei Yatsura displays low-level super-strength when sufficiently provoked. This developed from what was originally comic relief slapping and hitting.
 * Asuka of Neon Genesis Evangelion displayed this trope in the manga version. After bumping into a gang member in an arcade, she manages to easily kick him out the way and hold her own against several other big, burly men alone, with backflips and all. Admittedly she used the "Look Over There!" trick first. She never displays these moves again in the series, apart from a brief moment near the end of the same book.
 * In the case of Gally (or Alita, depending on who you ask) from Gunnm/Battle Angel Alita one would argue that her being a Full Conversion Cyborg justifies this... except that the vast majority of her opponents are as well, and are almost invariably much bigger than she is (frequently by a factor of 10 or more) and often just as advanced or nearly so.
 * It's called experience. She's done it literally for centuries.
 * Also, as Gally/Alita herself states at one point, Panzer Kunst (her fighting style) was created to fight larger opponents, specially larger cyborgs.
 * In a flashback scene in the manga, it's explicitly stated she's special, being one of the best practitioners of Panzer Kunst, and made all the more exceptional because she's female.
 * The Little Miss Badass of Mahou Sensei Negima, Evangeline A.K. McDowell, fits this well. During the Tournament arc, she tosses around all her opponents with ease using Aiki-jujitsu, a real martial arts technique, and strings. Using the two, she completely pins down Setsuna, who is one of the strongest characters in the main cast. But then she is a 500-year-old vampire, and has been learning the art for the last 100 years or so.
 * It's even implied that she learned the art from the man who originated it.
 * In Blade of the Immortal the deadliest swordsman is not Manji, the immortal main character, or Anotsu, the Big Bad, but Makie, a skinny, waif-like former prostitute who killed sixty wolves in one night at the age of ten. The trope is ultimately averted when Manji comments on how Makie's muscles are weaker than his and that her true advantage is her speed combined with her skill that she use to give her segregated Blade on a Stick more power through sheer momentum.
 * In episode 18 of the Tenchi Muyo! OVAs, Sasami—armed only with a staff she apparently kept in her hair—effortlessly defeated an armed and highly trained Galaxy Police operative, despite appearing to be no more than 12 years old and having shown no martial prowess whatsoever at any prior point in the series.
 * It's All There in the Manual. Sasami does possess martial arts prowess, it just wasn't mentioned in the OVAs before—after all, her mom is the head of Emperor's security and uncontested martial arts champion of the whole Jurai Empire. And it was mentioned in the supplements that Sasami DID train with Misaki, so she could take out a couple of GalPol mooks even without Tsunami's powers.
 * Nicely avoided in the anime Noir, adding credibility to a show with a implausible body count in most of its fight scenes. The whisper-thin ur-waif Kirika is one of the two most lethal human beings on earth. However, the writer never has her indulge in waif-fu. She always uses weapons to make her kills—including, in one case, a, never her hands or feet, and rarely shows more strength than might be plausible for her body frame.
 * Her weapon of choice is a Beretta M 1934, which fires .380 ACP, a fairly small round, typically used for backup guns only. The only common rounds weaker are .32 ACP and .22 Long. Much less recoil than a .45, or even a 9mm, usually.
 * Ofcourse her sheer ability to dodge bullets, and general use of acrobatics still very much enter her into this category. Ditto for Chloe, who also fights roomfuls of enemies with firearms with only tiny throwing knives.
 * Yuki Nagato of The Melancholy of Haruhi Suzumiya has combat skills and power belied by her schoolgirl appearance. This is due to her reality-hacking powers. (this fanfic describes her as "Agent Smith's niece.")
 * The "Agent Smith's niece" part probably stems from the fact that both are sentient programs and use programming to give them whatever skill or power they need to win
 * The titular heroine of the anime Solty Rei is a young, seemingly defenseless, girl with a Mysterious Past who "adopts" a bounty hunter who "saved her life" - who is able to take out a fifty-foot mecha piloted by two Mooks in the second episode. With one punch to its fist, which was in the process of trying to punch through her to her adopted protector. You don't want to mess with her.
 * And don't forget her very next move, where she hurled it into the stratosphere.
 * Although skilled primarily in the use of firearms, the child assassins from Gunslinger Girl are capable of punching a guy in the face hard enough to break his neck. Justified in that they're cybernetically enhanced to the point of having superhuman strength/speed/reflexes and being virtually bulletproof save for their.
 * While they are fast and strong, Triela's training scene implies that they are not really that skilled. Triela's the best hand-to-hand, and a burly instructor kicks her butt comprehensively. He then asks for (and gets) two weeks to teach her properly. After which she kills a trained assassin with a two-finger strike.
 * Averted in The Daughter of Twenty Faces. Although the titular 90-pound heroine Chiko is an Action Girl, her action mostly involves acrobatics and escape, not fighting people directly. Her trainers even point out that she can't hope to fight big burly men directly in hand to hand combat and if she must fight she has to rely on using their momentum against them and the like. Being explicitly told during training to aim directly at the groin area also helps.
 * Her fighting becomes more Waif Fu-like later in the series though.
 * Anita of the R.O.D the TV is very strong, capable of stunning a "vampire" by throwing a book into his face breaking his nose from five meters away without using her paper powers, and she can knock out grown men 3 times her size. Her fighting style was developed by animators via "observing monkeys and the Chinese Royal Acrobats." This is likely due to her
 * Anita was actually the only paper sister in that episode who could use her paper powers because they are
 * Anita does this trope again and is also shown to be a walking "Got Milk?" advertisement when she plays sports at school and throws a scorching fast ball across two fields into the catchers mitt.
 * I believe, in the dub at least, this was further emphasized by the catcher himself, as he said, "Dear god," in a very stunned voice.
 * Meow from Kazemakase Tsukikage Ran is a very slender young lady, who barehandedly takes out entire gangs of armed Mooks if sufficiently provoked. She still often plays the role of Damsel in Distress to the protagonist though, if the plot so desires.
 * Gender inverted in the manga and film Tekkon Kinkreet. The two boys, White and Black, are only skinny, unassuming ten-year-old boys, but they manage to take down grown, gun-wielding adults with nothing more than a length of pipe and some incredible jumping skills.
 * Technically, all female fighters in Ranma ½ save Cologne, as they're small, slender Japanese teenagers - and Akane and Ranma themselves are the tiniest of the bunch. Made explicitly obvious when they take on the humongous Dojo Destroyer and Pantyhose Taro.
 * In the first episode of Pokémon, Misty pulls Ash out of the water with a fishing rod, throwing him over her head in the process. A massive case of Fridge Logic.
 * Sapphire from Princess Knight Hand Waved for 1950s readers by her having an extra "male heart."
 * In Toradora!, Taiga's doll-like appearance doesn't prevent her from handing out Megaton Punches.
 * In a way, it's subverted later when in an actual contest of strength, Ryuji easily pins her to a wall.
 * Ayumi from Hatsukoi Limited has the build of an ordinary schoolgirl and the kicking power of a martial artist. Even the thug-like Misao is impressed with her kick.
 * Eri Kisaki of Detective Conan, in her first appearance, literally throws a muscular opponent three times her size across rooms and through walls. Her daughter Ran is also skilled in karate, but she's more of a Cute Bruiser variety.
 * A 15-year-old schoolgirl named Saya Otonashi may not be particularly intimidating, but there's a very good reason she's often mistakenly referred to as Blood The Last Vampire.
 * Intentionally averted in Ouran High School Host Club. Haruhi, dressed as a boy, tries stopping two guys messing with some girls. The host club and Tamaki especially get really pissed at her for it. Some cry Values Dissonance or worse while others call it realistic and a good message.
 * Values Dissonance can be avoided however by the fact that at the end of the episode, neither Tamaki (who reprimands Haruhi for doing something foolish and dangerous) nor Haruhi (who doesn't see how helping people in trouble could be bad) concede fully to other's views.
 * One could argue that in that situation the options were three girls in equal amount of trouble, or just Haruhi herself; she did help the others even though that put her in danger instead - and arguably her full intention.
 * Hunny is a good male example; looking like an elementary student, he's a fierce fighter who once took down six or seven armed and armored private police officers with no weapons, and they didn't even stand a chance.
 * Magical Girl Lyrical Nanoha Vi Vid has Vivio, Einhalt, Rio, and Corona, who are all 10 to 11 year old little girls that practice Strike Arts, the Mid-Childan Martial Art. For fun, they play "Who can displace the most water from a lake with a single punch above the water". Einhalt was able to make a five-meter tall waterspout with hers, temporarily making it rain in the area, complete with accompanying rainbow.
 * In fact, before the series, Einhart spent her days picking fights with experienced fighters who are all bigger than her even when she's in her Adult Form, and all of whom proved no match.
 * Izumi Curtis of Fullmetal Alchemist. Looks like a typical housewife. But manage to to set off her Hair-Trigger Temper (which isn't real hard) and you're in for a pretty solid ass beating. And you better pray your don't make her angry enough to use her alchemy...
 * And then there's May Chang in the manga, a young teenager approximately the size of a toddler. She kicked the ass of Edward Elric, an uncannily ripped (at least for his size) master of martial-arts and alchemy, as well as that of Ed's brother Al, who is a SUIT OF ARMOR.
 * Sailor Moon's Makoto Kino isn't that huge a Huge Schoolgirl, but can take out grown men when provoked.
 * In the second half of the first episode of Kimagure Orange Road Madoka shows how well deserved her scary reputation when she takes down about five times her mass in juvenile delinquents intent on beating up Hitomi-chan.
 * Several characters from Gokusen learned the hard way not to underestimate one Yamaguchi Kumiko.
 * Kallen of Code Geass generally does her ass-kicking in a Mini-Mecha, but is quite formidable in hand-to-hand combat as well... even wearing a bunny suit.
 * C.C. also knows some action moves.
 * Itsuki of Heartcatch Precure is a judo practitioner (her grandfather owns the school and she was planning to take over when her brother fell ill). She effortlessly tosses Kumojacky over her shoulder during an encounter way before she became Cure Sunshine!
 * A Certain Scientific Railgun has Kuroko Shirai, a first-year middle-school student who is capable of taking out heavily-muscled men twice her size (she only uses her teleportation ability a little bit). Her team leader Mii Konori is limited to Badass Normal levels of martial arts but is still more capable than anybody she's gone up against hand-to-hand.

Comic Books

 * In a late chapter of Bone, effortlessly lifts a Vedu warrior (easily twice her weight) over her head and throws him, presumably aided by her powers as the Awakened One.
 * Canon Immigrant X-23. Well, what do you expect from an Opposite Gender Clone of Wolverine?
 * Cassandra Cain, aka Batgirl III. You could fit her in a backpack with a little folding, and she's been known to flip seven-foot-tall five-foot-wide monsters around by their teeth.
 * This depends on who's drawing since she is sometimes drawn with Muscles.
 * Still counts as even then she would have trouble making 110 pounds.
 * Hit-Girl in Kick-Ass. She is trained in martial arts and firearms as well.
 * Given the vagaries of comic book art, just about any unpowered female will probably use this at one time or another, as quite a few artists simply refuse to draw women who look like they could carry a milk carton, much less win a fight. Combined with a tendency toward hyperthyroidism in male portrayal, this led to some especially egregious examples of Waif Fu in the 90s.
 * Lois Lane has a Military Brat background, which helps explain why she can get away from the occasional mugger on her own, but it was carried to ridiculous levels in one story when she single-handedly storms a guerilla base commando style to save a Brought Down to Normal Clark.
 * Sin City has Miho who is described as being 90 lbs and barely clearing 5 feet. She has thrown men through the air with her kicks and is strong enough to leap off a rooftop and shove swords through a car roof.
 * Apparently, she's one of the "gods" of Sin City. Being a deity might be the only way to explain her 90 foot vertical or surviving a grenade going off under her feet without a scratch.
 * Spider-Man himself provides a very rare male version of this. Due to his powers, he often dances around his opponents without getting hit. This is more obvious when fighting the likes of the Hulk or the Rhino.
 * Mary Jane is a skinny, femmine looking actress. She also had self defence training from Captain America (comics) and has no problem kicking the butt of any mook that tries to put her in the distressed damsel role.
 * Song in the Image comic book Epic Kill is shaping up to be this. As an individual who doesn't really use weapons, she's considered a national security threat.

Film
"Off with your head!"
 * In the movie Kick-Ass, the heroine Hit Girl takes this to Matrix like levels of combat skill. She is by far the best fighter in the film, much more skilled than the protagonist.
 * The quote above comes from the Firefly movie Serenity, where River's Super Soldier programming is activated by The Government manifests when she receives her activation signal (a "Fruity Oaty Bars" commercial) at the Maidenhead bar. She proceeds to wipe the floor with everyone in the bar, including resident Big Guy and Badass Jayne, who takes a shot at restraining her but gets a painful Groin Attack and a serving tray to the head that knocks him flat for his trouble. She is only deactivated when her brother Simon speaks a code-phrase that serves to knock her out. Her impressive capabilities come from a combination of Psychic Powers, extreme intelligence, and intense conditioning, which drove her insane. And that's not even mentioning what she does to the at the end of the movie, or the episode War Stories where she shoots three bad guys with her eyes closed. Also, in the comic Better Days, she kicks an Alliance commando in the teeth while he's sneaking up on her. Without looking.
 * Fiona from the first Shrek film.
 * DOA: Dead or Alive
 * Dragons Fire and Ice: Kyra, who looks like a series of toothpicks in a red catsuit and only 5 pieces of armor plating, fights against a massive horde of exceptionally large Vorgans.
 * Wong Fei Hung's skinny old aunt in Drunken Master.
 * Also, the whole Eighth Drunken God's being the most bad-ass and being a woman flaunting her body, with moves such as "putting on make-up" and "pretty girl looks in mirror".
 * Although in some versions of the actual myth, "she" is actually a man in drag.
 * Jen Yu from Crouching Tiger, Hidden Dragon, most memorably in the restaurant scene.
 * Zhang Ziyi is often gets typecast as a Waif Fu Action Girl.
 * When she appears to be a simple servant in Hero, it probably didn't convince anyone.
 * Her role in House of Flying Daggers.
 * Pulled off rather believably in Doomsday. When Eden Sinclair (played by Rhona Mitra) gets into close combat, she either dodges most attacks from opponents bigger than her (rather than parrying them) and/or uses some kind of weapon that's realistically useful against a stronger opponent.
 * Pretty much every martial arts film starring 5'3" Cynthia Rothrock. Rothrock is a multiple World Karate champion (although technically in forms and weapons demonstrations, not matches), and in most films will get the stuffing beat out of her by much larger bosses or Dragons before eventually emerging victorious. Rothrock herself has said that her movies are just movies and that a similarly skilled man would beat her every time in real life.
 * One of Sandra Bullock's early roles, in Demolition Man. She takes out one of the big strong super-violent thugs with a single kick. And how did she learn this move, living in the ultra-pacifistic society that has outlawed violence? She watched a Jackie Chan movie.
 * Short Round from Indiana Jones and the Temple of Doom. On his road to the mine cart, the tiny kid beats the crap out of numerous opponents, including extremely robust thugs.
 * Another male example: In Star Trek III the Search For Spock, Sulu beats up a security guard about twice his size who called him "tiny". Sulu tells him "don't call me tiny."
 * Three Ninjas. Despite the fact that the main characters were kids and not girls, they used the style. And one of the sequels had a girl who excelled at Waif Fu to the point that she curbstomped one of the ninjas in a tournament fight.
 * Chocolate (2008). Zen, a small Thai autistic girl whose Disability Superpower is to absorb martial arts from movies and TV shows. The entire movie is her beating up hundreds of people larger than her with muay thai. The actress supposedly spent 2 years learning enough muay thai to make it look realistic. The film handled her smaller size well - often, she uses it to her advantage by taking the fight into narrow spaces where her opponents have trouble moving.
 * A few of her expressions recall River Tam. She also appears to emulate a few martial artist celebrities, Bruce Lee among them, which stands to reason given her method of training.
 * The actress JeeJa Yanin herself qualifies; the ending credits show that all action was performed at full speed without stuntmen/women (leading to many injuries and hospitalizations.) Cuts not withstanding, what she appears do to on film she actually did in front of the camera.
 * Kate Beckinsdale's Selene in the Underworld series. Her counterpart in the prequel, Rhona Mitra's Sonja, however, is a Faux Action Girl.
 * The Angels in the Charlie's Angels film series use martial arts to defeat whole roomfuls of enemies. In the TV series, the Angels rely on more realistic tactics, but Drew Barrymore Doesn't Like Guns.
 * The teen/tween in the archive in Blade. She looks about 12 or 14 and she kicks Blade so hard he falls back. She even plays helpless, scared and cute when he first sees her, then kicks him through some Soft Glass.
 * Melody from the Josie and the Pussy Cats movie.
 * In some movies, i.e. Freddy vs. Jason, Crime And Punishment In Suburbia, and even Man Of The House, 5'1" Monica Keena seems very capable of taking down someone at least twice her size, though in her case, it's less Waif Fu, and more Waif Brawl.
 * From Balls of Fury, Maggie (played by Maggie Q) takes out a handful of martial artists, prompting Agent Ernie Rodriguez (played by George Lopez) to actually say "What does she weigh? Like 40 pounds?"
 * Leeloo (played by Milla Jovovich) in The Fifth Element.
 * The basic premise of Heroic Trio was to cram the three most popular waifs in Hong Kong into one kick-ass movie.
 * Alice in Wonderland, played by Mia Wasikowska, who looks like River Tam's even waifier sister, dons a shining suit of armor, and beheads the friggin' Jabberwocky(who, to add even more to the HSQ, is voiced by Christopher Lee).


 * Presumably due to Unstoppable Rage, the titular character in Blood Night: The Legend of Mary Hatchet manages to kill at least six asylum employees (five of them orderlies and/or security guards) barehanded. It's averted in the case of her daughter (played by the tiny Danielle Harris) though; once disarmed, the Final Boy easily overpowers and strangles her to death as she rather ineffectively wails on him.
 * Hanna uses Le Parkour to confuse and separate her enemies, her agility to dodge their stronger blows and her Tyke Bomb Training from Hell to exploit any opening instinctively.
 * In Iron Man 2, Natasha Romanova blows through a building with a combination of non-lethal weaponry and improbable martial arts - all in the time it takes Happy Hogan to take down one guard with conventional boxing technique.
 * Happy is at least enough of a bad ass boxer to be Tony Stark's bodyguard in the comics (until Iron Man got the job) while in the movie he is relegated to "put-upon chauffeur." Naturally, he's not match for Waif-Fu Lucha libre moves.

Literature

 * Kiki Strike of Kiki Strike.
 * Lisbeth Salander in the Millennium Trilogy is 4 feet 11 inches tall and looks like a child. She's no ninja, but happens to be very good at avoiding getting hit, sneaking up on people, and incapacitating her opponents, whether it's with stones, golf clubs or nail guns.
 * Lieutenant Karrin Murphy in The Dresden Files is 5 feet tall and a hundred pounds soaking wet. She's also The Big Guy. This is because she's highly skilled in aikido, which uses an enemy's weight and momentum against them.
 * And it goes Up to Eleven when she, especially in Changes.
 * There's also "Lydia", the mysterious client in Grave Peril - when possessed by a demon, she's easily able to throw Harry around, even though he's much bigger. Being Harry, he comments that this shouldn't work.
 * Mariel of Redwall. She's a mouse, probably aged about twelve in the first book, and has been kept as a slave for quite a long time, yet she's able to beat up seabirds with nothing but a length of knotted rope.
 * A lot of the Dibbuns, most prominently Baby Dumble, who was fighting crows in diapers. (Though admittedly he wasn't actually very good at it.) Or Bragoon and Saro, who left home to kick ass when they were still Dibbuns and don't come back 'til they're old, after which they kick more ass
 * Justified in R.A. Salvatore's Cleric Quintet with Danica Maupauissant. She's described as "barely topping 5-ft and 100 lbs., with a mop of bouncing strawberry-blonde hair." And she kicks the tails of everyone. Priests of Oghma, who are very accomplished wrestlers (and most are at least three times her size) make her wrestle them before they tell her where to find what she wants in the Edificant Library. She always wins. The reason this is justified within the series is because she's a Dungeons & Dragons 2nd edition Monk. Loosely translated: Shaolin monk on crack.
 * Nellie of The Avenger. Weighs maybe a hundred pounds sopping wet, tosses men more than twice that weight easily, thanks to her extensive knowledge of jujistu and other martial arts. Her job is made easier by the attitudes of the 1930s making it hard for male opponents to realize how effective a combatant she could be.
 * Vin in Mistborn is a tiny teenaged girl who, by the time the trilogy ends, has taken out just about everything nasty the Crapsack World can throw at her. She is one of the titular mistborn, and as such possesses powers including but not limited to superhuman strength, speed, senses, telekenetic control of metals, and a Jedi-like ability to see the immediate future.
 * Vin has an advantage even over other mistborn, not just because her small form gives her greater agility and balance, but because her super-strength is more concentrated, giving her a proportionally stronger punch. She basically uses the Square-Cube Law to her advantage. Her small size is also useful for stealth, since mistborn are typically assassins and spies. The only disadvantage is in the manipulation of metals, since if one is too heavy she will be moved instead.
 * Bast the Wood Elf John Ringo's Council Wars series who's about five feet tall and looks like a fourteen-year old girl although she's not. Justified in that she's a genetically engineered killing machine with about a thousand years of combat experience.
 * Juliet from Artemis Fowl. Justified in that she is a Butler.
 * Jo Clayton's Serroi, who's maybe four and a half feet tall. Justified in that she does have extensive martial training, and relies more on speed and agility than strength.
 * The Vord Queens in the Codex Alera series look like slender, beautiful women due to  They are also incredibly fast and strong and are able to take hits from titanic crossbows that can punch through heavy armor or horses and keep going. Then again, they're not human, but the powerful, monstrous leaders of a species that has eaten entire worlds.
 * Also, Kitai, a young White-Haired Pretty Girl with the strength of a grown man and the ability to take almost anyone in a fistfight. This is justified by the fact that she's a Marat, not a human, and she's pretty well-muscled to boot.
 * Matty Roh of The Heritage of Shannara is quite tall, but her slender build and reliance on a rapier make her fit this trope. Her strategy relies on dancing around her opponents before going in for the kill. Makes things rather interesting when she teams up with the much more physically powerful Morgan Leah.
 * Jacky Faber of Bloody Jack fame often uses her skinny young waif act to get out of tight situations. Most of her adversaries who fall for this are fooled into thinking she's a Just A Girl, to their detriment, since she's a former street rat/war veteran with a "shiv."
 * Dairine Callahan from the Young Wizards series. At eleven she offers to take on her fourteen-year-old sister Nita's biggest adversary, Joanne, and beat her up (Joanne and her cronies had just beaten Nita up pretty badly)-- and although she doesn't do it, it's made quite clear that she can, and even Nita admits it.
 * Nita and Kit are both also examples. The reason Nita doesn't fight back is that although she has the skills, she knows that she's outnumbered and fighting back will only make it worse. But when she gets a hold on wizardry she gains self confidence—and a much, much bigger adversary than Joanne. And she kicks butt. And the magic is just as cool as physical skill, because fighting with magic costs you just as much energy and strength as fighting physically. Magic is just more... dignified. Well, aWoM kind of subverts that in Nita's battle with Aurilelde, but still.
 * YW has so many examples of this, you can't name them all.
 * The Valkyrie of Immortals After Dark live and breathe this trope; as one of the books puts it, they are "small and delicate-*looking*. It's a biological advantage. You'll never believe what they can bring to a fight".
 * Nico from The Spirit Thief in the Legend of Eli Monpress series. She's small and painfully thin, but her demonseed abilities give her inhuman strength, speed, healing, and the power to step through shadows.
 * Alice from the Twilight books.
 * Played realistically in the Belisarius Series: Shakuntala is extremely fast and nimble, the prize pupil of India's most lethal martial artist and phenomenally strong for her size. However, she is tiny (about 90 pounds soaking wet) and that bites her on the arse a number of times.
 * Pity from the Sinister Six Trilogy was able to give Spider-Man quite the beating despite being very petite.
 * Nina from Reserved For The Cat; she's a trained ballerina, and knows that jumps, spins, and kicks can be useful both in dancing and fighting.

Live Action TV

 * Firefly: River shoots three guys not only with her eyes closed by from behind cover while facing the other way after taking one short glance.
 * Buffy the Vampire Slayer: Buffy and the rest of the Slayers.
 * Scully from The X-Files often fell into this trope, seemingly capable of holding her own in a throw-down until the writers needed her to be kidnapped (which also usually means when they needed Mulder to suffer).
 * Max from Dark Angel, although she was a transgenic trained-from-birth Super Soldier.
 * Happened to Lana Lang on Smallville in the later seasons, with the very brief and none-too convincing explanation that she had taken a self-defence course. Had actually happened to her as early Season 4, but she was possessed by Isobel Thoreaux, a Wicked Witch and Dark Action Girl, at the time, thus justifying it. Lois is also prone to this, although it's somewhat more believable thanks to her Military Brat status. Kara of course, has Super Strength going for her, and Tess a) is more of a bruiser, and b) just plain cheats, thus averting the trope.
 * In the Doctor Who episode The Mind Robber, Zoe gets the super-powered Karkus to work for her by defeating him in hand-to-hand combat, despite being much shorter, having no powers, and showing little tendency towards physical combat before. One explanation is that they're in a dimension where Your Mind Makes It Real, and Zoe does have a very good mind.
 * Alternatively, she had seen the Karkus is comic book form and knew he didn't truly exist, so he had no power over her. The Doctor had never heard of him, so he wasn't able to fight the Karkus the same way, but he could confidently claim that the Karkus' "anti-molecular ray disintegrator" gun was complete rubbish and couldn't possibly work, at which point it ceased to exist.
 * The titular character in the episode The Doctor's Daughter displays this.
 * Cameron in Terminator: The Sarah Connor Chronicles. Justified by the fact that she is a Terminator. Cameron is played by Summer Glau, the same actress who played the "90-pound girl" mentioned in the above quote.
 * Interestingly enough, Cameron's small size when compared with other Terminators does actually play into the fight scenes; when she tackles another, larger robot in a straightforward slugging match she typically loses unless someone is helping her. It's only when she outmaneuvers or surprises a Terminator (for example, the "water delivery" Terminator, or Stark, or Cromartie the first time) that she wins without outside assistance.
 * Fiona from Burn Notice is a small girl and no stranger to combat, but this trope is averted as she is a Combat Pragmatist. On one occasion she was supposed to take down a large man to interrogate him later. She tried using a stun gun but he disarmed her in the attempt. She managed to get it back while he was trying to wrestle her down. After the narration explained that stun guns will shock you if your target is holding onto you, Fiona proceeded to stun the guy anyway.
 * Kira in DS9 is only of average size and build for a woman and doesn't seem very threatening from her appearance alone (her behaviour is another thing, though). However, she practically grew up as a resistance fighter an in the last season is a certified Colonel Badass. She's probably the best hand to hand fighter on the entire station after Worf.
 * Echo, Sierra, and November from Dollhouse depending on what imprint they're loaded with.
 * Although even in fights were Echo has the right imprint, she still gets her small size used against her, as in she gets picked up, carried and shoved or thrown against something. In one fight to the death Sierra got into it was half luck that she escaped alive. November seems not to feel pain in assassin mode.
 * Sam of iCarly despite being a 5-foot tall tweenager, is somehow strong enough to take down several security guards, a girl bully much taller than her, and move a giant piece of a destroyed wall with one hand.
 * Robin on How I Met Your Mother appears to have this ability, throwing down Ted in one episode.
 * Parker in Leverage normally avoids combat, but cracks open a case of waif fu to fight a Serbian gangster. As per the trope, when he gets a grip on her she's in serious trouble, but when she breaks free she's able to use her greater speed and agility to knock the crap out of him. Although later in the series, she seems to primarily use stun guns whenever she needs to engage in combat. Though she is able to deliver a beat down to protect Hardison.
 * Pick any of the female Power Rangers. They tend to be noticeably shorter than the male rangers, but they can hold their own in a fight, even with the occasional kidnapping.
 * Joy Turner may come off as a typical trailer park mom, but years of Springer and a mean right hook make her a force when she gets really pissed. Just ask Earl's ex, a trained bounty hunter.
 * Samantha Carter of Stargate SG-1, while 5'9" and so not precisely short, is blonde, adorable, shorter than all her SG-1 teammates by at least three inches, and at least twenty pounds lighter to boot. And yet she kicks at least as much ass as they do on a regular basis. Did we mention she blew up a sun??
 * Phoebe from Charmed does this occasionally but it's justified since she'd been studying martial arts for years. In a few season 3 episodes Prue gained this as well for no apparent reason.

Music

 * In "Game of Death", an animated short featuring the band Gorillaz, Noodle (a 10-year-old girl) effortlessly throws Russel, who is extremely large.

Professional Wrestling

 * Prior to Gail Kim's original WWF debut, there were plans to bring her to compete against the guys using her waif-fu like high flying abilities. Unfortunately, there's a difference between hype music videos and actually performing in the ring, and while her moves may have been impressive, her unreliability at hitting them properly and consistently (read: she botched a lot) put an end to those plans.
 * WWE also had plans to bring Shantelle Taylor in wearing a bodysuit, win matches against guys, and reveal herself as a girl after she'd been winning. They never did this, however, and she ended up wrestling in TNA as Taylor Wilde - then retiring because of how little money she was making there.
 * Ivelisse Velez used this whenever she competed as a face in intergender matches on the independents.
 * Rey Mysterio whenever he's up against larger opponents. Though he's actually larger than most normal men, he just looks like a dwarf next to the much huger big guys. Ditto for Evan Bourne.
 * Current WWE Divas that employ this style - Kelly Kelly, Alicia Fox, Eve Torres, AJ and Naomi. In Eve and Kelly's case it's justified since they're both former gymnasts (and Eve is a blue belt in Brazilian Jiu-Jitsu) while Naomi is a former dancer.

Tabletop RPG

 * Most Tabletop Games systems make little or no statistical distinction between males and females during character generation, Dungeons & Dragons being a prime example. Sex aside, a decently leveled midget (dwarf, halfling, gnome…) will be able to easily trash whole groups of giants (orcs, ogres, gnolls…) with their bare hands.
 * That said, these games will provide systemic support for this, with smaller characters having bonuses to dodge and hit larger characters whose advantages lie in their superior reach and damage.
 * Warhammer 40,000's Eldar, despite being thinner than the average human, are at least as strong as one. This is explained partly by different muscle configuration, and partly by their speed; since net force equals mass times acceleration, this means that they can actually hit fairly hard, even if their lifting capacity is not all that great.
 * Played with when considering Aspect Warriors like Striking Scorpions, who wield chainswords that increase the strength of the wielder, Farseers and other special characters.
 * Even more so with the Kroot, who are as strong as a power-armoured space marine.

Video Games

 * Sakura Kasugano: Her Waif Fu is stronger than yours! See her (with a minor assist by the ever-lovin' blue-eyed Thing) SMASH puny Hulk and Peter Griffin!!
 * Her rival, Karin Kanzuki, is out to prove that her Waif Fu is stronger than Sakura's. Canonically, she succeeds, but decides that the real importance lies in the thrill of the fight.
 * Those two have a real Laura/Nellie thing going on.
 * What makes Sakura's Waif Fu status even more apparent is that she had seen Ryu fight in the first Street Fighter tournament and managed to mimic the Hadouken, Shoryuken and the Tatsumaki Sempu Kyaku so closely to the real thing. The kicker? Capcom itself has stated that she's quite a prodigy, considering it took Ryu years of training to perfect said moves. To say that she knows Waif Fu is an understatement.
 * In the Soul Calibur series, petite pre-teen Amy can apparently block blows from weapons delivered by enormous men wielding axes, swords and maces.
 * As well as Talim, Xianghua, and Taki.
 * Used to hilarious excess in The Misadventures of Tron Bonne. After declaring how she'd been taking self-defense courses since the last time they met, policewoman Denise proceeds to manhandle Tron's Humongous Mecha by judo throwing it around town.
 * Tales of Symphonia's Presea Combatir. That axe has got to weigh more than she does...
 * Also Colette from the same game. You don't see as much as it with her as you do with Presea, but if you can watch her pick up a huge, muscular man that probably weighs twice as much as her without ANY effort whatsoever, then say she isn't strong, you're insane. Granted, she has angel powers, but still, it's damn impressive.
 * Karol from Tales of Vesperia too. Granted he's male and the trope is slightly subverted at the beginning. But throughout the game you can give him swords that are BIGGER THAN HIS ENTIRE BODY and he can still wield them!
 * Sophie from Tales of Graces, despite being only about 5 ft. tall and looks like a skinny little twig, can plow all her enemies into the ground with her gauntlets like there's no tomorrow.
 * Etna, Yukimaru, Sapphire...Oh to hell with it; just about every young female character from the Disgaea series. Muscle is entirely optional
 * Nessiah, from Yggdra Union, is one of the exceedingly rare male examples of this trope. Not only is he tiny—he's stuck in a set of heavy chains that should by all rights make any form of combat impossible. And yet he manages to thrash the player's entire army with ease. The fact that he's a mage isn't even an excuse, as most magic-users in Yggdra Union have very low attack stats to match their lack of physical strength.
 * Tohsaka in Fate/stay night. Look at her twig arms and mediocre height and tell me, do you honestly believe she could pull off the admittedly awesome things she does in hand to hand combat? Also Saber, but to her credit when she isn't buffing herself with magic strength she's actually a good deal weaker than either Shirou or Tohsaka. It'd be even harder to believe otherwise from her considering she's about five feet tall and weighs ninety pounds.
 * Of course, in Saber's case physically weaker doesn not reduce her insane skill.
 * Ciel usually just chucks swords. Okay, kinda believable. But then she lugs around a gun that weighs more than she does, and it doesn't seem to slow her down that badly? Uh, okay. At least Arcueid is a vampire and has magical super strength or something. Actually, Arcueid admits outright that most of her strength has nothing to do with muscle mass and only considers herself as 'athletic' without it, enough to dodge Shiki's knife if he were to try something.
 * Konoko, the slightly-built protagonist from Oni, makes a habit of beating up on burly stormtrooper types.
 * Just about any fighting game allows even the smallest girl to throw the biggest and fattest man. An egregious example would be the Dead or Alive series where you can kick/punch/throw a character into a wall (or right through it, breaking the wall) from quite some distance, or down to a lower stage, defying the laws of physics.
 * This is one of the more Egregious examples (Skip to 2:07.)
 * King of Fighters series has Hinako Shijo, a half-Russian Japanese schoolgirl... who is a sumo wrestler!
 * Penelo from Final Fantasy XII is very petite compared to the rest of the party, but she can be formidable in her own right, and you can even give her a BFS.
 * In Tekken female characters tend to be equally sized, but Xiaoyu is probably the smallest, yet is a very tough - and quick opponent.
 * Of course, we also have Gnome and Goblin females in World of Warcraft who are just the tiniest of the females out there in the Alliance and Horde respectively. But when played as a warrior they become tiny titans who can tank raids as well as any Draenei or Tauren male... the largest player characters possible on the same sides of the fence as the aforementioned females. And with the application of the proper talents, these mighty minis will wear full plate armor, and wield a gigantic two handed weapon in each hand, all the while moving like a ballerina on the battlefield. Not to mention what they can do with straight up DPS as rogues, death knights, or other melee combat classes. Forsaken females may also qualify for this trope as well when one considers that there is literally little left to them but skin and bone, looking as if they could fall apart with a good hit from a thick stick.
 * Skyrim. Bretons and in the previous game, Wood Elves, are both smaller then many of the other races, but can prove just as competant in melee combat if built right.
 * Female Elves and Dwarves in Dragon Age are both much smaller than Humans (either in build or height), but aren't to be reckoned with. The Warden in particular. Subverted in Dragon Age 2 - Merrill (who is very small/thin) is a mage, but she can be built to withstand a lot of punishment (making her a weirdly effective Stone Wall), especially compared to Anders, the fragile human male mage.
 * No one is saying The Boss is a waif, but compared to Volgin, she is lighter, a little shorter, and has 10 millions less volts of electricity flowing through her. None of that stops her from throwing him to ground very easily. Also of mention is Paz in Peace Walker, if Snake is too...forward on their date, she sends him flying with a slap.
 * City of Heroes allows you to make any class any size, but since they can all kick ass it's not impossible to meet up with tiny female front-row fighters.

Web Comics

 * Twice Blessed has Pella Brightwing, a pixie warrior princess who in her first fight in the comic takes out two robots the size of houses.
 * Megatokyo has several examples:
 * Ping, who is a robot girl.
 * Miho. In addition to various improbable acrobatic feats such as dodging an electric ray, disabling it, instantly vacating the scene in a matter of seconds, and walking quite calmly on telephone lines, she also grabbed a car by the hood and crushed it by flipping it over with one hand.
 * Yuki as well. Although she has not displayed excessive strength or combat skills she also can walk normally on telephone wires (until she realized where she was and promptly fell). She also apparently possesses the power of teleportation which she used to steal, among other things, a whole rent-a-zilla...twice. She also defeated a small horde of Zombie Rangers by throwing appliances at them. Including a washing machine. A remarkable feat, considering most conventional weapons would most likely have been unequal to the task.
 * It has recently been directly stated that Yuki is indeed a Magical Girl, as always suspected. Very likely Miho is one as well.
 * Candi Levens, and just about everyone else female in her world except for Claire Rauscher. Partially justified in that the game engine only allowed for three different physiques to begin with.
 * And because there are only so many free GameMods to fix that problem with The Sims 2.
 * Rain from the webcomic Triquetra Cats. Even before getting her magic powers she is still a black belt champion in 9 different martial arts (including one not normally taught to humans) despite being a 14 year old girl with the build of a 10 year old girl.
 * Tristan from Angel Moxie. This is unexplained at first; later she discovers
 * One of the main female characters of the Polish Kokoart, Kitty, shows her powers at Waif Fu many times. The first time it's in the 13th and 14th strip ( and ) where after being insulted by calling her "nuts" by the main character, Cherry, she chases him and his friend. Cherry ends up in hospital (2 arm fractures) after being hit with a truck. When the friend (still unnamed after 3 seasons of the comic!) tells her that the truck was maybe just little too much, she responds, "The truck was by accident".
 * In 'Schlock Mercenary characters are trained in martial arts aboard a 31st century starship. This becomes much more sensible (eight years later, go figure) when an angry mob sets upon a girl engineer whom readers even mistook for a child when she was introduced. She holds a green belt in shotokan karate and her clothing is a standard issue set of powered armor. There were pieces on the ceiling...
 * Sluggy Freelance's Oasis.
 * Chen-Chen in Harkovast is a lot more dangerous then she looks, at one point smashing a mans skull with her fist!
 * In Seventy Seas, on only the second page we see Nikol Mimagi (a.k.a. Mimagi Niku), a 13-year-old ninja who is easily the most lethal of the three main characters even though the other two are adults.
 * Everyday Heroes: During her childhood, Jane got tired of getting picked on by her older brothers. (Of course, it helps that her mom was a ninja.)
 * Slightly Damned has Kieri, who spends much of her debut injured and unable to speak, right up until the point where someone says the magic words, breaks a binding enchantment and gets stabbed.
 * Sydney of Grrl Power, even without her powers.
 * Lourdes of Mystic Revolution manages to throw novice player L33t Ninj4 hard into a wall, with a whip, from across a gorge. She also hits a Dryad Berserker (claimed the strongest class-race combo in the game world) clear off the ring, with her bare fist. Granted that she is built like a moderator.

Web Original

 * Ninjai. Despite being a young kid, he is capable of killing much bigger enemies and surviving things normal people wouldn't be able to.
 * Being a Super-Hero School full of mutants, Whateley Academy has several examples, including:
 * Toni Chandler (Chaka) is fourteen, female and slender, but her superpower is control of Ki, and the ability to pull extra Ki out of the Earth. In the short story "Duel Damsel", she challenges a superstrong upperclassman who looks like a blond Sasquatch, because of what the guy did to her friend. She pummels him without even using her most powerful techniques. She's also beaten an unstoppable super-werewolf, clobbered people wearing power armor, taken out a superpowered ninja...
 * If you must mention Chaka, you must mention Chou Lee. Bladedancer isn't even a mutant, just a "baseline" imbued with the Tao, trained in awesome Wudan martial arts skills, and a wielding a sentient sword that can cut anything. She's taken down the same aforementioned ninja, people in armor, demons, cyborgs, random attackers, and just about everything she's fought since she arrived at Whateley.
 * Ayla Goodkind (Phase) is 5 ft tall and weighs anything from nothing to a little more than a ton, according to her mood. This mutant ability allows her to toss around opponents many times her size.
 * When mentioning Phase here, we have to mention "Boston Brawl II" in which she beat up a forty foot giant and then used his body like a flail, much to the other supervillains' regret.

Western Animation

 * Gwen from Ben 10 is a ten-year-old girl, yet still capable of holding off the Monster of the Week on her own if needed, thanks to some martial arts lessons.
 * Starfire from Teen Titans, who was as strong as the much bigger, cybernetically-enhanced Cyborg. Interestingly, this was explained as not being a superpower inasmuch as an ability of her species.
 * Robin is closer to fulfilling this trope, as he is explicitly a slim, adolescent Badass Normal who can toss around a super-strong giant made of concrete as if it were styrofoam.
 * The heroes of the Sat AM Sonic the Hedgehog cartoon were realistically limited for the most part; but Sally Acorn periodically managed to jump-kick or toss a seven-foot robot in a way that a three-foot rodent probably shouldn't.
 * Jade Chan of Jackie Chan Adventures through some yet-to-be-discovered law of physics is able to bring down people fairly easily at times. One time she brought down a strong government agent in one kick that her uncle was having trouble with. She brought the big sumo Tohru down in one kick as well, causing the house to shake. Despite all this she still has to be contained by the villains and/or Jackie. This is probably due to her being the Reincarnation of the Dalai Lama.
 * Kim Possible calls on "sixteen kinds of kung fu" and a lot of cheerleading practice to batter armies of henchmen twice her size—despite her looks, she truly is that strong.
 * Toph of Avatar: The Last Airbender is a little, BLIND 12-year old. She routinely kicks everyone's tails. In fact, the only fight she's ever in where she loses is against the protagonist, and that's only because she had never fought an Airbender before. Hell, the only time she ever really gets injured is by It's true that she almost never makes direct contact with those she fights, and uses Earthbending instead, but still. Hell, she's the most powerful and talented Earthbender in the entire Avatar universe.
 * Let us not forget the final episode where she not just metal bends the bridge door of a fire nation's zeppelin, she
 * Ty Lee also kinda-sorta qualifies for this trope. She has no Bending ability, she carries no weapons, she's a skinny perky cutie ... and she can totally incapacitate you by poking you in the shoulder.
 * It should be noted that her style has absolutely no strength involved, it's purely speed and pressure points; she has no need to knock anybody out (especially when they'll go nearly BSOD at the loss of their bending))
 * Arguably Valerie from Danny Phantom. Aside from being stated to be a ninth degree level black belt (despite being only fourteen), she routinely kicks powerful ghosts' butts on a daily basis. At one point she engaged combat on her own battle suit, possessed by a ghost (and managed to hold herself in said battle pretty durn well).
 * Well, Valerie isn't exactly a small girl herself, she's got some meat on the bone.
 * Sue Ellen from Arthur is only 8 and one of the smallest kids in 3rd grade, yet has good enough martial arts skills that she can flip Binky, the biggest and heaviest kid in her class, as if he weighed nothing.
 * Spinelli from Recess

Real Life

 * Because they don't hold anything back in a fight, animals (of either sex) can be incredibly strong for their size. A 25-pound monkey will nearly always beat a 150-pound man in an arm-wrestling contest, and a dog the same size can pull its owner to the ground by yanking hard on the leash.
 * This has more to do with muscle tissue construction. It is believed that Humans (on an evolutionary scale) traded a lot of strength for endurance and temperature regulation. (Believe it or not, on a hot day a human can keep moving long after most any other animal has collapsed of heat exhaustion.) So, in the end, Humans Are Special.
 * The partial reason for this if you're wondering is that our bipedalism decouples the processes of locomotion and breathing, so we have better control of breathing while running than quadrupedal animals. Also if you watch a toddler learning how to stand and eventually walk, you can see that walking bipedally is pretty much learning to control your falling. It's easier to run a long ways when gravity is doing a portion of the work. And Now You Know.
 * Likewise, it's believed the first hunting method used by humans was to run after prey until they'd faint from exhaustion. That's right, our ancestors could beat antelopes at running. Well, distance running; the antelopes could beat us in the 100-meter dash any day of the week, but an antelope would die of exhaustion trying to run a marathon. Being endurance runners also helped in gathering foods which may be separated by vast distances. One scientist thinks this may be the reason why the posterior is the focus of so much erotic evaluation.
 * This is still done in some remote regions.
 * It only works in warm climates however. In colder regions wolves and wolverines have the advantage. Fortunately, we don't hunt wolverines.
 * It's also our superior temperature regulation from sweating. It's not so much as running the prey to exhaustion in general as running the prey specifically to heat exhaustion. (The researchers who first studied this tried to replicate the technique themselves with Pronghorns in North America's temperate climate and got pwned. When it is done with gazelles in the height of the sub-saharan African summer, it works.) The ability does come with a cost though - sweating requires lots of water. Humans are much more dependent on having reliable continuous sources of fresh water than most other hot climate adapted animals.
 * There are some times when, if you know the right self-defense moves, size doesn't matter. There's an instructional video called "Just Yell Fire" which is designed to teach teenage girls these in hopes that they can use them to defend themselves against potential sexual predators. (Basically, it boils down to: go for the groin, eyes and ears.)
 * They do matter to a degree. How much they matter in any given situation will vary. Obviously, if you've got an advantage (especially a significant one), then of course such things don't matter.
 * Size and strength matter a lot for a lumberjack match, but if you're just trying to nail someone in the groin and run until you're in clear view of people they're a lot less significant.
 * Aikido is a martial art that works to the advantage of the smaller person; it's largely based on leverage - throws, pins, and dodging. A shorter person will have an easier time with some of the techniques, whereas foot-taller people will end up basically scraping their knees to do it.
 * This is true, but only for some techniques. There are techniques (look up e.g. Irimi Nage, there are many good YouTube videos out there showing what it looks like) that work better when the person performing the technique is taller. If you're too short, you'll have to work harder to bring the person you throw to your level. However, in broader terms, there is one indirect and paradoxical advantage to being short and/or physically weak, no matter the technique. If you don't have your strength to rely on, you'll have to learn the proper execution of techniques. Initially, stronger people have an easier time "forcing" a technique, but a good sensei will discourage that, because this approach will only take you so far. In the end, strength but can sometimes make a difference and be helpful (Ueshiba Morihei, the founder of Aikido, is said to have been a very strong man for most of his life).
 * Wing Chun is a style which was said to have been inspired by a woman and utilises techniques that are effective when used by lighter individuals.
 * Ballet dancers, especially female, look like nothing but they're all lean muscle. Dancing an entire ballet is said to require as much strength and endurance as being a linebacker in an NFL game.
 * Yet the number of ballerinas drafted to the NFL is rather low.
 * On the other hand, ballerina Fanny Elssler, when attacked by a robber, kicked him in the gut and killed him.
 * The point here is probably that you need to be equally as fit to do either.
 * There is a type of hand-to-hand combat which despite having many of its elements distributed among various military style martial arts such as Krav Maga, doesn't actually have an official name anywhere. It is frequently taught to personnel who are likely to have need for it and it is based mainly on weaknesses in human physiology. It is completely useless in what are sometimes referred to as "Social" fights which are best exemplified by the classic "Let's go outside and see who can kick who's butt" type of fight. It is intended only for what may be called "Asocial" fighting in which there isn't any issue of ego, only of survival. The training involves the learning of the various point on the human body that are susceptible to damage and how to attack them in ways which will limit your opponent's ability to continue the fight. It's effectiveness is it's limitation, since using these sort of methods will cause serious physical injury and possibly death - you can't just box with a man in this way. Techniques include the forceful imposition of fingers or other objects into the eye socket, causing severe and permanent damage to the eyeball; and the intentional breaking of critical body parts, including but not limited to the temples, larynx, knees and collar bones. No matter the size or strength disparity between opponents, if the larger combatant cannot walk, see, breath or think, then he cannot fight.
 * William E. Fairbairn described this style of fighting like "Get tough, get down in the gutter, win at all costs...I teach what is called Gutter Fighting. There’s no fair play; no rules except one: kill or be killed." His way of fighting could be taught in a few practice lessons to green recruits, because it consisted of rather simple moves: those which are forbidden in boxing and other martial sports - exactly because they are aimed to kill the opponent, not to beat him.
 * The complex art of stick fighting is reduced by Fairbairn (in Get Tough!) to just five strikes - all of which are aimed to smash the opponent's face, spear his brain through the jaw or break the larynx. Unless you somehow live in the Roman Gladiators' age, this may have you quickly imprisoned for murder.
 * The difference between the aformentioned "social fight" and someone fighting for their life is considerable. A larger person might engage in fighting for sport or over petty arguments, but a smaller person will try to avoid physical conflict. Therefore if a smaller person is actually in a fight, they're probably completely engaged in fight or flight response, with all of the awesome ass kicking power it can bring.