Most short kendo practitioners. While the big guys may be able to hit harder, the smaller ones move faster and hit more areas, which is what counts in kendo. Case in point: a 5'1 man beating a 6'3 guy within ten seconds. Quite impressive.
This is even more prominent in competitions, where points are only granted for perfect technique, not strength. In fact, training with the katana teaches the wielder to strike with finesse and smooth, flowing motions, since relying on muscular strength can very easily damage the blade. In other words, katana wielders are trained to end fights with the first attack, using as little exertion as possible.
This is also the reason why women and men practise and often fight together in same series. Size or strength really doesn't give any advantage in kendo.
Johannes Lichtenauer, one of the prominent Medieval figures in German School Of Swordsmanship considered an ideal knight to be rather small and concord in stature than big and well-built, and having rather stamina than strength. [Strong, tall and well-built men would make fine archers.]
Morihei Ueshiba, founder of Aikido. Many pictures of O-Sensei, as he is known, show him in the process of serenely◊ trouncing◊ people quite a bit taller and younger than him.
Nobuyoshi Tamura, former student of Ueshiba, sensei of the French Aikikai, an 77 years old quite small man (compared to his French and European student) who has no qualm about having his younger, taller and stronger students crawl to the ground.
Gozo Shioda, an early student of Ueshiba and founder of Yoshinkan Aikido, " was a small man, standing at around 5' 1" to 5' 2" (155–157 cm) and weighing around 102 lb. to 108 lb. (46–49 kg)", according to that Wikipedia page.
Muggsy Bogues managed to hold his own against many of the best basketball players in the NBA despite being 5'3" (160 cm) tall - the shortest man to ever play in the league. Bogues had several pictures of him with the tallest NBA player ever, the 7'7" (231 cm) Manute Bol. There was a 28-inch (71 cm) difference between their heights◊. Bogues and Bol were actually teammates for one season—Washington Bullets owner Abe Pollin was the Bill Veeck of the NBA.
The 5'7" (170 cm) Lionel Messi and the 5'5" (165 cm) Diego Maradona are generally agreed to be two of the 10 greatest soccer players ever.
Israel is one of the tiniest countries in the Middle East. It's also a well known military powerhouse and is acknowledged for having the uncontested best-trained airforce in the world. Likely because it is almost always dealing with violence in some way or another.
Similar to the Israel example is Finland, Switzerland and (during the Cold War) Sweden. All nations with populations below 10 000 000 inhabitants and armed forces counting numbers close to the million.
This trope may be a reason why Singapore requires its male citizens to undergo two years of military service.
Many combat specific soldiers are shorter, around the 5' range or even less, and a Napoleon complex isn't uncommon. But in a Real Life aversion, it's a common complaint among drill sergeants in Combat Arms OSU Ts that 'the skinny ones break too easily', while the overweight recruits develop muscle mass from fat with fewer injuries.
Nepalis are known for their small size. Despite that the Gurkhas have a remarkable reputation as soldiers. During the 60s the Gurkhas usually carried the American M16, rather than the British SLR. The reason for this was that the M16 was lighter and easier for the Gurkhas to fire.
Audie Murphy At 166cm/5'6", the Marines and paras rejected him for being too short. His company commander tried to have him sent to a cook and bakers' school after basic, but he'd have none of it. He went on to win every military award (some multiple times) in the US up to and including the Medal of Honor. And a few French and Belgian decorations on top of all that (little trinkets like the Légion d'honneur). And he had malaria at the time.
Simo Häyhä, at 5'3'' (160cm), was likely the greatest sniper of all time. He is officially credited with killing 705 Soviet soldiers over roughly 100 days of combat.
Finnish Air Force. Never consisting of more than two fighter regiments, one bomber regiment and one reconnaissance regiment, it nevertheless managed to score more than 1500 confirmed victories against the Soviets and create 106 fighter aces in WWII. Even today, Finnish pilots flying F-18 Hornets managed to score 100-6 against their NATO opponents in Frisian Flag 2013 excercize.
Likewise, the Israeli Air Force. There are more Israeli jet aces than there are jet aces together in the rest of the world.
The destroyer USS Johnston in the Battle Of Samar fought so hard that when it was sunk it was reported by the Japanese as being a heavy cruiser of the Baltimore-class, a ship class nearly seven times the displacement of the typical WW2 destroyer. The Johnston not only managed to cripple the Heavy Cruiser Kumano by blowing off it's bow, forcing the heavy cruiser Suzuya to stop to assist it. Then after already taking heavy damage the Johnston engaged a Japanese cruiser and destroyer column in order to save the retreating escort carriers.
The Destroyer Escort Samuel B. Roberts at the Battle Of Samar made its heroic attack run, passing the now heavily damaged USS Johnston as it was retiring from similar attack. After expending its 3 torpedoes damaging one Japanese Heavy Cruiser, Samuel B. Roberts maneuvered so close to a Japanese heavy cruiser that the Japanese crew could not depress their guns low enough to return fire, leading to considerable damage to the Japanese cruiser. The Samuel B. Roberts was eventually crippled in the exchange, and while retreating, was hit and sunk by the Battleship Kongo. It was said of the ship that it was the Destroyer Escort that fought like a Battleship.
Note: The Escort Carrier White Plains and an unknown aircraft finished the job for the little Sammy B,White Plain blowing up Chokai's type 93 "Long Lance" torpedoes with a well-placed 5/38 shell(5 in. diameter, 38 cal. length barrel), and the aircraft dropping a bomb in the forward machinery room, according to the Other Wiki. The destroyer Fujinami had to scuttle her.
Double Note: Chokai lost all hand. The Fujinami was later blown up with all hands, which, by the way, still had all of Chokai's survivors aboard.
The wolverine is a non-human example of this. It's maybe about the size of a medium-sized dog or a large badger, and can take down reindeer. Wolverines have been seen bullying an entire pack of wolves and stealing their food, and there have even been documented cases of them fighting off bears! Against a wolverine's hell of a bad temper, the eponymousSociopathic Hero is comparatively more of a Deathbringer the Adorable.
The shrew is among the tiniest mammals in the world, and they can take down things that, proportionately, would ruin a wolverine's day.
Humans, too. 80 kg man can hunt almost any prey using tools. Without them, however, a man still can defeat an alligator or survive an encounter with a bear, if lucky. If you take account on the muscle mass, humans are incredibly strong.
While size does make a major difference among evenly skilled fighters in the martial arts scene, the smaller competitors are still formidable fighters capable of impressive feats; many ostensibly lower weight class fighters have fought in the heavyweight divisions and done quite well. Also, when weight classes were introduced to competitive judo, many of the small judoka left the sport, saying that building the skills to overcome larger opponents were an integral part of it.
Bruce Lee. The man was seriously tiny and scrawny for what was considered a good build for actionherobadasses. That really didn't stop him, and it was theorized that, pound for pound, he was probably one of the strongest men alive.
Martial arts masters, physical trainers, etc. all universally note that the key to Lee's power wasn't the unnecessarily large muscles one usually associates with "strong men;" instead, Lee's body was toned so perfectly that he had somewhere in the range of 0 to 5% body fat, with every muscles being trained solely for absurd explosions of strength and speed without any wasted effort or force. The result was a musculature more defined and proportionally perfect than most anatomical models.
Chris Paul is one of the best and most feared players in the NBA, despite being one of the shorter ones (at 6' in height).
Boxer Manny Pacquiao is 5'6", and tends to come weighing in the mid 140 pound area. He's one of the best boxers in the world. You can underestimate him because of his size, goofy smile and friendly manner if you want to, but he will fuck you up if you do.
Most boxers in his weight class would qualify. Sure, they'd probably lose to heavyweights who are trained boxers, but some schmoe off the street isn't likely to fair so well, even if he outweighs the light weight by 50 pounds.
5'1'' MMA fighter Nakai Rin certainly counts.
Foil Fencers are often going to be better if they are both short and skinny, and they are harder to hit, and can get in close more easily. Short historical fencers who know that they're doing are nothing to sneeze at, either, when you realize that you have to bend at the knees (bending over exposes your head) to hit anywhere except for the head, which is far easier to defend against than your legs, which is their primary target.
Rhinoceros beetles. They are about 60 mm long, and can lift up to 850 times their own weight.
Liam Hoekstra: The world's strongest toddler. He has a rare genetic disorder that makes him have a (incredibly high) metabolism, and has 40% more muscle than the average kid. In short: he's three and has a six pack. How does that make you feel, nerd?
The Ratel, or Honey Badger, is an animal only three feet long. It is also the most feared animal in Africa. Honey badger don't give a shit about lions, cobras, etc. since their skin is thick enough to protect them against most animal stings and bites and actually too tough to be pierced by a spear or an arrow and it can withstand several machete blows, they have been known to chase away adult lions and steal their kills, they raid henhouses by actually tearing off the planks from their walls... short of actually being bulletproof, there is little they can't withstand.
Many small ice hockey players (David Krejci, who ended his career with the Boston Bruins, and Theoren Fleury, who most famously played for the Calgary Flames) can play a style better suited for players way larger. Krejci's hit opponents so hard, he gained the nickname of Wrecking ball.
Maurice Jones-Drew from the Jacksonville Jaguars. He was passed over in the draft until the second round because most scouts thought he was simply too short (he's listed at 5'7" and that's probably being generous). He's consistently been one of the NFL's top rushers, while spending most of his career on Jaguars teams that didn't have much else of anything in the way of offense.
Doug Flutie was the same height as Jones-Drew, and was thought to be too small to play QB, partly because he theoretically couldn't see downfield over his 6 foot plus offensive linemen. In spite of this, he had a respectable career in the NFL, and stars in one of the most memorable plays in college football history.
Leopards are the smallest of the big cats, and not only kill animals that are bigger than they are, but have been known to drag carcasses twice their own weight into trees. See here for a leopard carrying a zebra nearly as big as itself straight up a tree and making it look totally effortless.
Philippine national hero Jose Rizal, author of Noli Me Tangere and El Filibusterismo, is only 1.5 meters tall. He is not only a polymath, but he is also a gym buff, a gifted fencer, a sharpshooter, and a wrestler. He challenged a bigger bully to a fight and won.
Machine example. The "FQ" series produces anywhere from 300 to 400 horsepower. The engine is a two liter straight-4. Most consumer level cars with that engine produce under 200 horse power.
Modern Formula One engines are restricted to under three liters. They produce well over 600 horsepower.
Most modern turbocharged engines (as in "designed from scratch to be turbocharged", not as "someone added a turbo") are incredibly strong and also light for their size: VW/Audi 1.8T (it can be easily modified to run over 400hp), Subaru 2-liter boxer (even street versions kick serious ass, but it has been modified for drag racing to give a whopping 700 hp), Renault Megane RS 2-liter turbo and so on.
Any car with small exterior dimensions/short lengths and powerful large engine sizes do count. Shelby Cobra, AMC Gremlin, and Chaparral 2J, for example.
Peter Dinklage is a man with dwarfism, but he's also a hell of an actor.
Alexander Veljanov, a Macedonian-German singer and the lead vocalist of the band Deine Lakaien.
South Korean golfer KJ Choi is a bit on the short side at 5'8, especially standing next to peers like 6'4 Ernie Else or 6'5'' Dustin Johnson. Despite this, he's always had a reputation as a reasonably long hitter (though not as long as Johnson), probably as a result of him being a competitive power lifter as a junior, who could squat 350 lbs as a 95 lbs 13 year old.
Dustin Pedroia of the Boston Red Sox is known for his short stature. His listed height nowadays is 5'8, though USA Today once listed him as 5'7 when he was in college. The ambiguity isn't help by his rumored desire to be measured while wearing his baseball cleats, standing on a hard surface. Either way, Yankees fans give him endless shit about his height and he's one of the best second basemen in the league. In addition to being a very good fielder and "contact" hitter, he's not entirely without power at the plate.
And, though he's much less of an action star than the other two, the 5'7' Tim Roth.
4 of the most prominent members of the Bones Brigade, Tony Hawk, Rodney Mullen, Lance Mountain and Steve Caballero, were kids at the time when they were recruited but Steve was the most prominent example as Stacy commented in The Bones Brigade An Autobiography that Steve was the smallest skateboarder he ever seen, even compared to other kids like Tony Hawk, yet Steve is able to do tricks that he shouldn't be able to do, hence the reason why Stacy wanted him to be on the Bones Brigade. Even when all grown up he is still consderably shorter than most people◊.
Pretty much any dive bomber in WW2. It was really cheap to build, but any well-placed bomb could destroy a ship.
The Voltigeurs of the Grande Armée were a whole unit of these. They could be no taller than 5'3' but had to be extremely sturdy and skilled with a musket. There were also specially selected for their aggressiveness, so you could say that they were soldiers of Napoleon's army with an actual Napoleon complex.
For a while during the later parts of the Cold War, the Panavia Tornado could certainly count. Although it wasn't small by European standards, it's smaller then many American Fighters, and could carry more ordinance then most of them until very recently. However, where an American attack on an Airfield could require several aircraft performing various tasks to take out, RAF and Luftwaffe doctrine only required two Tornadoes, each packing a JP 233 Bomblet Dispenser. After just one pass by both aircraft, a Runway would be both cratered, and mined, rendering it useless for days or weeks. Oh, and to add insult to runway cratering injury, the Tornado is a multi-role aircraft, and is just at home in a dogfight as it is in a Runway attack.
The JP 233 has since been pulled from service citing several advances in cruise missile technology that can mitigate the risk to the Tornado and its crew. On top of that, when the bomblets are dropped, the JP 233 has to be carried back to base, not exactly a good thing to have when you're trying to outrun a bunch of very pissed off fighters that managed to get off the runway before you ensured they couldn't return to it.
Oh, and to really give some nightmares, the Tornado can also carry up to four B61 Nuclear Weapons. In short, one Tornado can level four cities in one mission. Sleep well enemies of NATO!
While not exactly a small aircraft by any standards, the B-25 Mitchel of US Army Air Force fame in World War II was still smaller then most other bombers of the war, but it was probably the single most versatile bomber of the war as a result. The most widely used version, the B-25J, was used in just about every attack role imaginable. Aside from the defensive machine guns (which the B-25 had in abundance), the bomber also had 4-6 .50cals fixed forward for strafing duties, with a later version even mounting a 75mm cannon in the nose. It would be this bombers small size, and still impressive bomb capacity (3,000lbs), that would make it the perfect choice to launch the Doolittle Raid with, since the bomber was small enough, andnote after shedding unnecessary weight light enough to launch from the Aircraft Carrier Hornet. Compared to the damage B-29s would do some years later, the raid itself did little physical damage, but B-25s were still able to send the message to Japan that they really DID wake a sleeping giant.
It should be noted that B-25s were so versatile, easy to fly, and so maneuverable, that several foreign Air Forces bought up surplus Mitchels, or bought some during the war and held onto them. The last B-25 was retired from active service in 1979. Not bad for a medium bomber that first flew in 1940.
Tarantula hawk wasps are strong enough to drag around tarantulas over three times their size.
The HAL Tejas is a positively tiny warplane designed by India—it has an empty weight of only 6,500 kg. The single-engine Tejas has a maximum takeoff weight of 13,200 kg, just over twice its empty weight. For contrast, the US-made twin-engined Raptor weighs 19,700 kg and a maximum takeoff weight of 38,000 kg, which is a bit under twice its empty weight. In case you are under the impression that the Tejas buys this relatively greater lifting power at the expense of agility or speed, it is in fact a highly maneuverable supersonic multirole fighter, meant to challenge both enemy aircraft and ground targets. On top of that, two of the featured weapons in its loadout are fuel air explosives and incendiary bombs. That means that this little monster will cheerfully bring a disproportinately large amount of fiery death to your door and remind you exactly why the named it the "Radiant".
Likewise, Folland Gnat and its descendant, HAL Ajeet. Gnat was originally designed to be a budget alternative for bigger and faster fighters, and fighter version of Gnat F.1 was first operationally flown by Finnish Air Force in 1958. It proved extremely manouevreable and a skilled pilot could easily challenge MiG-21. The Indian Gnats proved superior to Pakistani Sabres and Starfighters, and the indians developed Gnat further into HAL Ajeet ("Unconquerable"). Finnish Gnats were withdrawn from service 1972 and Indian Ajeets in 1991.
Mantis Shrimp and related groups. On average, they grow to less than one and a half feet long. They are able to swing their claws with an average acceleration of over 100,000 meters per second (330,000 feet per second). Because of this ability to swing their claws so rapidly, they also generate cavitation bubbles that collapse with enough power to produce instant forces of 1,500 newtons. This means that even if their attack misses, the resulting shock wave will be enough to stun or even kill their prey.
Dromaeosaurs. Even the biggest of them were small by dinosaur standards, but with their speed, agility and wickedly sharp claws, they were capable of taking down pretty hefty prey; there's a fairly famous fossil of the smallish, birdlike Velociraptor locked in battle with a much bulkier Protoceratops.