Dragon Ball: Bulma will single-handedly perfect time-travel, launch the space exploration industry, and artificially produce energy comparable to a small celestial body if it will help Goku or Vegeta. Gotta love that girl.
Washuu from Tenchi Muyo! In the original OVA she actually isn't much of a gadgeteer — most of her time was spent in doing research so complex that the viewers were rarely let in what she was doing. The later TV-series increased her gadget-building role considerably.
Niea from Niea_7 was shown to have built a functional UFO out of trash materials, and powered by a regular AC power outlet. Unfortunately, it exploded once it was unplugged.
Irina Woods, one of Arika's friends and roommates from Mai-Otome, has taken a great interest in engineering. She even tried to build a giant house-cleaning machine to assist Arika with her punishment duty (which broke down almost immediately, but at least she tried).
Nina Einstein from Code Geass. She invented a NUCLEAR WEAPON in the last episode of the first season using the contents of a High School science lab! Granted, it was only semi-functional and broke down before detonation but still impressive In the next season she did build a functioning bomb... with disastrous results. By the end of S2 she builds an anti-nuclear weaponIn a month. It works, both for Lelouch and her fandom reputation (partially, in the latter's case).
Spanner and the future Giannini from Katekyo Hitman Reborn!. They can do anything. Including building giant robots and motorcycles which are as quiet as mimes.
Franky and Usopp of One Piece. Franky is much more advanced, able to build crazy machines and ship-enhancements, while Usopp has that original flavor, his best example being Nami's weapon, the Clima Tact.
B-Ko from the Project A-Ko series, who introduces a Humongous Mecha, complete with heat-seeking missiles, laser weaponry and titanium armor, with the nonchalant disclaimer that "it did take me most of last night to build". She's not bluffing, either: until she eventually settles into a Powered Armor suit, she spends about a week going through more and more elaborate new mechas on a daily basis.
For a Jidai Geki series, Ayakashi Ayashi has one hell of an example - Masurao, a member of the 'People of the Craft', proves capable of whipping up devices in feudal japan that would be considered revolutionary TODAY - including a fully-functional handgun made from paper. His Crowning Moment of Awesome, however, comes when he is pursued by the heroes through a construction-site, grabs some random pieces of wood and some tools without slowing, and craft them into an attack-robot to sic on his pursuers. Without ever stopping.
Hozuki from Galilei Donna. Built a fully armed and operational airship (shaped like a goldfish) in her basement, complete with holographic (goldfish-shaped) AI, among other things. And she did this when she was thirteen.
Amuro Ray from Mobile Suit Gundam is shown as being this, whether it's inventing Haro or designing the Nu Gundam in Char's Counterattack entirely from the ground up.
X-Men's Forge has the ability to intuitively determine how anything works, and by this point, after years of exposure to all manner of gadgetry, is able to whip up any manner of Applied Phlebotinum you can possibly imagine. We're talking Star Wars level.
He is also a shaman. This fact isn't brought up so much, because combining the two aptitudes leads to questions of why he has not whooped most of evil's ass by now.
Oh, but he has. He stopped the Adversary, an evil Physical God and banished it from the world. Twice. It's probably going to resurface soon now that Forge is dead.
The writers of X-Men: Evolution decided that wasn't Bad Ass enough and gave him the ability to transform his arms into any imaginable tool to help him make his creations. Considering the tendency of his creations to get away from him, it can be wondered if he's not as good as his comic and 1990s series counterpart or if he's simply a lot less responsible.
Angie from the superhero comic PS238 by Aaron Williams (author of Nodwick) combines the ability to make just about anything out of old cars and other junk with having the mindset of the cast of Pimp My Ride. Bling-bling and Explosive Overclocking tends to riddle whatever she ends up building, which is just the way she likes it.
And of the male (and not quite as explosive) type, the school also hosts Zodon and Herschel Clay, who both have significant gadget construction and tinkering skills in addition to (or due to) being prime examples of, respectively, the Evil Genius and the Mr. Fixit.
Brainiac 5. He's been described as a genius among a species of geniuses, the type of prodigy that comes along once in a millennium (which is how far the Legion is from the rest of The DCU). The solution and cause of a lot of the Legion's problems. Is currently working on rebuilding the economy of the United Planets and inventing a new way to break the speed of light.
Iron Man, who in turn inspired a Gadgeteer Genius (aptly codenamed Gadget) to build a tech-suit in her garage. Probably from a box of scraps.
In Astro City, Beautie's origin is revealed: she was built by a girl Gadgeteer Genius, the still more brilliant daughter of another Gadgeteer Genius. (Her father's reaction leads to Bad Things for both Beautie and the daughter.)
Not to mention the Junkman, who uses stuff that's been thrown out to create his devices (as he considers himself cast off by society because of his age). Despite the self-imposed handicap, he is one of the few villains in Astro City who actually win, as it is implied he gets away from his trial with the recognition he craved and all the loot he stole.
Alpha Flight supporting cast member Madison Jeffries has the mutant power to physically alter machines, metals and related inorganic objects, which he initially used as a mechanic. (His brother Lionel had a similar power over living tissue, which had gruesome results when he went insane.) Another more conventional genius was Roger Bochs, a paraplegic who used his tremendous scientific skills to build machines that overcame his disability - namely, the robot Box. When Madison took over Box, he used his powers to turn it into a Transforming Mecha whose forms were only limited by his imagination, and whatever materials he had that could be added to it.
Sonic the Hedgehog has Sir Charles Hedgehog, better known as Sonic's Uncle Chuck. He was the mechanical genius who invented the Roboticizer as a medical device. Too bad a certain rotund Overlander decided to sabotage it to Take Over the World...
The original, pre-Crisis version of Lex Luthor was the archetype of all comic book Mad Scientists, but he most displayed his juryrigging skills with his trademark jailbreaks. For instance, a substitute prison warden was dumb enough to get him to fix a printing press and he turned it into a tank like escape vehicle to smash his way out. Sometimes he would smuggle tools inside with him when he was carted off to jail — tiny tools hidden under a false patch of skin on his thumb for example — but he was perfectly capable of building an escape device without them.
In Warren Ellis's newuniversal (based on The New Universe), this is the power provided by the Cipher Power Tattoo. Of the three known bearers, one was a prehistoric woman who invented electric lighting and energy weapons, but believed they were gifts from the gods; one was this world's version of Tony Stark; and the most recent is Humongous Mecha designer Dr Jennifer Swan.
Batman is this to a certain degree. Though most of his larger contraptions (like a Satellite that monitors all meta human activity down to the slightest) are built by a subsidiary of his corporation, WayneTech, making this overlap with Crime Fighting With Cash. That being said, most of his arsenal (including the Batsuit) is designed and built by himself.
Most recently Static in the pages of Teen Titans. Previously, Static was just a very bright kid, but in Lobdell's Teen Titans, he's become a full blown Teen Genius: designing Red Robin's glider wings and creating a new costume from scratch for Kid Flash that prevents his powers from vibrating him to nothing.
Ted Kord as the Blue Beetle is the defining example of a gadgeteer genius superhero. He invented all of his gear himself, a lot of which was reverse-engineered alien technology (you think HTML code is tough?), up to and including a beetle shaped flying ship.Guy Gardner has even said that Ted was smarter than Batman.
This is the premise of the Polish series Pomyslowy Dobromir. The eponymous hero may not build giant robots or steampunk wonders, but he's still a kid who is apparently able to come up, from scratch, with the basic principles for a number of technological innovations (such as the spyglass or the gramophone) and build working prototypes from household materials, all within a matter of minutes.
In Nobody Dies, Asuka is reimagined as this since she never trained to be an Eva pilot. Here she actually demonstrates that college degree she claims to have in the original series, enough that Yui Ikari takes her on as a research assistant.
Hivefled: Equius and Sollux manage to create Alternia's first ever removable psionic helmsman rig. Nobody's ever bothered to even try before, and they hook one up out of junk they have on hand.
Chronomistress Out Of Time: Minuette, Time Turner, and quite possibly all members of the Order of Timekeepers are very good at mechanics.
Princess Trinity has Inkie Pie as an ingenious inventor (her creations include artillery and a Giant Mecha prototype), who nevertheless finds herself constantly stymied by her useless hooves. She dreams of inventing mechanical arms, but for the time being, she needs a two-armed minotaur assistant just to turn a wrench for her.
Sky Bolt from The Dusk Guard Saga. Her latest commercial design, The Alicorn, had to be reverse-engineered, because nobody understood how it worked exactly, and so she would have been the only one able to maintain it. Her pet project is an improved steam engine with estimated 250% power increase over regular ones. She plans to use it in The Hummingbird, a miniaturized airship.
Dr. Cockroach from Monsters vs. Aliens manages to build a working computer out of a pizza box and paper clip, and that's after an experiment turned him into a humanoid cockroach. If he ever gets his hand on a box of LEGO bricks and some uranium, watch out!
Word Of God on the DVD commentary says that Edna Mode is a mix of this trope and a fashion designer. She directs her genius toward the superhero costumes she designs.
Syndrome. There seems to be no limit to what he can build; moving walls made of lava.
In Epic, Professor Bomba has built gadgets that allow him to adjust to the "speed" of miniature creatures, allowing him to communicate with them.
Up has Charles Muntz, who has devised equipment that allows his dogs to talk and fly planes and amplifies their intelligence, and, prior to leaving for Paradise Falls, he had devised several other inventions for his dogs including automatic doggy-baths and walkers. Toward the end of the film it turns out he's not just a gadgeteer genius, but a sinister Mad Scientist.
Eggs shares a knack for tinkering with his adoptive family, The Boxtrolls. He seems to have inherited it from his biological father, Mr. Trubshaw.
Film — Live Action
Doc Brown, slightly crazy inventor and engineering genius from the three Back to the Future movies. Built a time machine in the form of a Delorean car. Then a second even more stylish time machine which combined a 19th century steam locomotive with anti-gravity and cold fusion technology from the future.
He turned a regular steam train into a time traveling steam train with nothing that didn't exist before the 1800s, except for a hover-board.
And his epically-impractical ice-making machine.
The Blade movies (especially Blade Trinity) have several characters who build high-tech equipment for the vampire hunters. Seriously... ultraviolet light bullets??
Q from the James Bond films. He's even the chief of an entire MI6 sector of Gadgeteer Geniuses.
In several of the novels by John Gardner, Q/Major Boothroyd's character is downplayed so Bond can flirt with his Hot Scientist assistant, Ann Reilly. Her nickname is "Q'ute," which explains a lot.
Tony Stark in the 2008 Iron Man movie (not to mention the comics it's based on) is depicted as a gadgeteer genius. He builds the power suit prototype and his own Unobtainium artificial heart using spare parts provided for the construction of a Jericho missile. In his own lab, he creates even more impressive gadgets.
Subverted with Dr. Loveless; most of the work is done by the scientists he has captured. He doesn't even hide that fact, but he is smart enough to find a way of surviving after being blown in half (albeit by his own prototype tank).
Gwen/Royal Pain from the super-teens comedy Sky High calls herself a "technopath." She demonstrates the ability to magically repair electronics, as well as presumably designing and building her own armored super-suit.
Harry Dresden frequently works with Michael Carpenter, a sturdy, talented carpenter who also happens to be a KnightoftheCross. Divine intervention is one of the perks of the job. But that man is not a Gadgeteer Genius. The man known as the miracle worker of the series is Mike, Harry's mechanic. He keeps The Blue Beetle running most of time, despite its proximity to angry wizards and angrier Eldritch Abominations.
Feliks Polon and his father in Feliks, Net & Nika. Their house is full of more or less useful gadgets, multiple functions are performed by robots, and basement is stuffed with things that don't work. Mr Polon works in government top secret tech center where he programs rockets and Feliks built huge humanoid robot called Golem when he was 15.
In the Discworld novels by Terry Pratchett, a recurring character is the befuddled genius inventor Leonard of Quirm (an obvious parody of real-world Renaissance Italian inventor and painter Leonardo da Vinci).
In Thief of Time, we encounter the gadgeteer Qu, an obvious parody of James Bond's Q.
The Wild Cards series features quite a few gadgeteer characters, such as Jetman, but in a subversion, the gadgets they make don't actually work. Some of them actually have no means of operating. The gadgets are just tokens that serve as a crutch for their powers.
Foaly from Artemis Fowl. He is stated to be the reason the People are still ahead of humans.
Even older example is Oscar Diggs, otherwise known as The Wizard of Oz. He had to rebuild all of his parlor tricks and theatrical illusions from scratch. In later books, he is shown to make all kinds of fantastic inventions, including a steampunk-era cell phone.
Soledad O'Rourke of Those Who Walk In Darkness is a specialist, only designing Abnormal Ammo. However, she deserves to be on this list after creating BLAM bullets, which "lock in on molecular structures in a state of hyperkinetic motion," turning in midair to target foes who possess Super Speed.
Tom Clancy's Net Force series, based on the name alone, would be expected to have a lot of these. And it does. But with one exception later destroyed, no one can best Jay Gridley.
In the novelization of Metropolis, Rotwang is one of these mixed with Mad Scientist Classic. He was Joh Fredersen's right-hand man in building the titular city, and in only a few years designed all its major technical achievements: the workers' underground city, all the machines, the reservoir, the subway, the road system, and the New Tower of Babel. (Even the soundproofing in Fredersen's office is named for him.) Even in his stagnant period following the loss of his wife Hel, he builds a mechanical replacement arm and a robot companion. Fredersen essentially imprisons him in the city to act as emergency technical advisor.
Brother Kornhoer from the second section of A Canticle for Leibowitz creates a working electrical generator and an arc lamp with wagon wheels, melted coinage, a bit of graphite, and some newly-recovered theoretical knowledge. The Isaac Newton-expy is floored to see it.
Cogs in The Grimnoir Chronicles books are exactly this. Unlike most other examples though, Cogs tend to be specialized.
The main character of The Chronicles of Professor Jack Baling is able to build a disintegrator gun out of parts from his microwave, flatscreen TV, laser pointer, refrigerator, and his wife’s hair dryer that plugs into any standard wall socket.
LaVerne Thorndyke, in the Lensmen series, is known in-universe for being this - and that really says something, when the universe in question is the trope namer for the Lensman Arms Race. He was the project leader for building at least three of the planet-destroying weapons in the series, among other things.
The District 3 boy in the The Hunger Games and Beetee (also from District 3) in Catching Fire. District 3 makes electronics and explosives, so, yeah...
Frankie in Angelmaker, she creates many a complicated and intricate device, but most importantly the Apprenhension Engine that defies all logic. She just happens to be working under the Big Bad.
Willy Wonka is a Candy Genius, which wouldn't normally qualify. However, considering he designed/built not only the Factory itself but such wonders as the Television Chocolate setup and the Great Glass Elevator, one suspects his skills go a bit beyond chocolate. And he has an army of Oompa-Loompas - some of which may have helped with or come up with the designs themselves.
The Doctor can save the universe with a kettle and some string, though he usually does so off-camera. He also has a knack for taking diabolical inventions cobbled up for some nefarious purpose and subverting their intended purpose, usually with disastrous results for the villain of the day.
In "The Day of the Doctor," Ten explains that he built the shape-shifter detector he's using himself. It also boils eggs at twenty meters and can download comics from the future.
The Doctor: I never know when to stop.
This was clearly an adaptation of his Timey-Wimey Detector from Blink. Which goes ding when there's stuff, and can boil an egg from 20 paces, whether you want it to or not. He's clearly added new functions since then.
The Doctor: I've learned to avoid chickens, it's not pretty when they blow.
In The Lodger, the Eleventh Doctor builds a Scanner using, among other things: an umbrella, a bicycle, a walker, a lamp, a broom, a canoe paddle, an ironing board, christmas lights, and a rotary clothesline.
It dates back at least to the Third Doctor; in "The Time Monster", he builds a device to disrupt the Master's temporal experiments out of a Moroccan burgundy bottle, spoons, forks, corks, keyrings, tea leaves and a mug. (Apparently it's the shape and composition of the components that matters, not the function.)
Drax, a fellow Time Lord in "The Armageddon Factor," builds an effective Shrink Ray out of a random pile of junk he has lying around. He also designed the intelligent battle computer that's been waging genocidal war for the last umpteen years.
Also Professor Yana, the Master in disguise, who builds a rocket's computer system "out of food and string and staples."
Just about everyone in the town of Eureka at some point, on the television show Eureka, except for Sheriff Carter.
Micah from Heroes is a ten-year-old boy whose mastery of machines allowed him to make his own circuitry for his computer. This is later explained to be his superpower, control and knowledge of machines.
Pixel is able to build almost anything, from hovering cameras, to a device that can transport people into storybooks, to a remote control which can control literally everything, including random electronic things he has in his room to people. In Secret Agent Zero, the 007 parody Episode, he played the role of Q. And he is 9 years old.
Robbie Rotten can build anything out of anything he has in his lair. He even has a Microwave which creates the inventions for him.
One of the most famous gadgeteers of TV was MacGyver, although he was more of a tinkerer. The series that spawned the term "MacGyvering." Usually worked alone, without a sidekick. Oddly enough, though, there was an episode of MacGyver where he teamed up with a classic Gadgeteer Genius girl — an ultra-intelligent schoolgirl who could match him move-for-move.
It doesn't come up much, but it's implied that Joel Robinson, of MST3K, as well as a number of other characters on the show are this. In the theme, they even say that Joel used the "special parts for controlling where movies begin and end" to create the four seemingly-sentient robots, three of whom watch movies with him.
The original premise of the show was that the Mads (mad scientists) stranded Joel in space specifically so that they could steal his inventions. In several episodes, during the Invention Exchange, Joel complains when the Mads steal his ideas. The Invention Exchange didn't really last long after Joel left, however... instead of inventing stuff, Mike would fill his time by either confusing the Mads (for example, by pretending to be a drive-though restaurant, or shilling them "bold" BBQ sauce), or attempting to escape (for example, challenging Pearl to a game of three-card Monty).
The crew of Mythbusters should DEFINITELY count, especially Grant and Jamie.
Power Rangers has had several characters who could apparently create/repair Humongous Mecha in a matter of hours. The most egregious example is the Ass Pull of two fully-functional copies of a mecha introduced out of the blue. Cam's just that good.
Then there's the fact that Billy Cranston, the first Blue Ranger, invented a collection of wristwatches that could be used both as personal communicators, and could remotely activate an alien teleportation grid. Villains aren't the only ones who could Cut Lex Luthor a Check.
The most impressive part? He put the teleportation thing in by accident. He was just trying to connect to the alien communications network. The day after meeting the aliens for the first time.
Red Green of The Red Green Show aspires to this. Usually he doesn't make it and his inventions backfire horribly, but on rare occasions they actually work. A forklift built out of a K-car is truly a wonder to behold.
Scholar Mek of Spellbinder began the second series by designing and building a transdimensional boat... when he was supposed to be making a set of musical jewels for the Dragon Lord.
Basically every Chief Engineer from Star Trek is an engineering genius: Scotty, Geordi La Forge, Miles O'Brien, B'Elanna Torres, "Trip" Tucker.
Starfleet Engineers in general seem to have a reputation for this. In the Deep Space Nine episode "Rocks and Shoals," a wounded Vorta says of a broken transmitter system, "It needs repair, but I'm willing to bet that you've brought one of those famed Starfleet engineers who can turn rocks into replicators." Further, in the Expanded Universe there's an entire novel series called "Starfleet Corps of Engineers."
Presumably, the dry dock engineers are geniuses too, since they manage to survive and repair all the alien tech that all homecoming vessels seem to be infested with.
Plain and simple, Garak was a man of many hidden talents. Give him toys to play with and he could come up with anything. It becomes a plot point in a couple of episodes, most notably in the double-episodes "In Purgatory's Shadow" and "By Inferno's Light"; where Enabran Tain used his own unique brand of Gadgeteer Genius to alert Deep Space Nine to the survival of various Alpha Quadrant prisoners in the Gamma Quadrant and then Garak had to finish what Tain had started after Tain dies because he was the only one with the skill, expertise and creativity to convert a system into something it originally wasn't designed to do so that they could escape prison. Oh, and he had to do it all while suffering chronic claustrophobia, too. Even the Klingons were impressed.
Spock was also sometimes expected to be a Gadgeteer Genius, even with only primitive materials to work with. In "City on the Edge of Forever," he expresses his frustration at having to do this with 1930's technology: "I am endeavoring, ma'am, to create a mnemonic memory circuit, using stone knives... and bearskins."
On the original series, while Scotty did an impressive job MacGyvering and was a remarkably fast and thorough Mr. Fixit, plot-resolving new technology usually required a teamup with Spock, who was otherwise fairly consistently presented as a theoretician and IT man.
Justified with the Enterprises because, as capital ships, their officers are the best of the best from an organisation spanning hundreds of planets, or in the case of Enterprise, at least the whole of Earth.
For Deep Space Nine, Miles O'Brien was actually Chief Petty Officer on a Federation outpost, and they don't hand those positions out readily. For Voyager, well, Maquis, being outlaws with secondhand gear, have to do a lot of MacGyvering, and apparently Torres was just the best at it.
Lampshaded in the 2009 movie: Scotty is just a little too smart for his own good, having beamed "Admiral Archer's prize beagle" across the galaxy for a bet. To allow him time to wait for it to arrive, he's sent to the Starfleet equivalent of a remote Alaskan radar station. Apparently, Porthos was going to re-materialize at the very end of the film, but it was cut for time, alas.
In Time's Arrow Data proves his gadgeteer skills when he builds a functional temporal scanner using 19th century materials (and probably a few of his own circuits).
Tuvok earns his Gadeteer Badge when he improvises several phasers from parts scavenged from sonic showers and food dispensers when the crew is imprisoned in a artificial environment aboard a giant space station in Displaced.
In the Torchwood episode "Fragments", it's revealed that Toshiko Sato once built a working sonic screwdriver from incorrect blueprints.
Claudia Donovan from Warehouse 13. H.G. Wells is a villainous version of the tropes.
As noted above, Artemus Gordon on The Wild Wild West cobbled together all sort of useful gadgets for his partner James West to use.
And unlike the film, the series Dr. Loveless was this (See the widgets and blueprints around one of his early episode labs— they include a blueprint for a turbofan engine. Another ep has a tagline from Artie mentioning some crazy invention to throw sound and pictures through the air...).
Siroc from Young Blades is known for his (frequently anachronistic) inventions, including a submarine, a machine gun, a metal detector, a bomb concealed in a hollowed-out watermelon, and a machine that generates static electricity by turning a wheel of artificial feet wearing socks so that they rub against a static-generating material.
One of the Mascots of Top Secret is Prof. Dzemik note (his name is a rather complicated pun on a Polish celebrity), who originally was facetiously created as an expert who responded to the readers' technological questions, and also starred in the magazine's comics where he was usually a plot device who invented the time machine or exposited on a dimensional transporter that was the basis of a story's plot.
In Noob this apparently comes with being a neogician who put plenty of work in his or her optional inventor job.
Urza and Mishra, the Brother Artificers of Magic The Gathering, build enough weapons and doomsday devices in their lifetime to leave their world a nearly-blackened cinder by the end of their lives.
Likewise, Venser and Tezzeret. Heck, there's even an entire creature type (Artificer) based around making insane gadgets.
The Sons of Ether/Society of Ether from Mage: The Ascension are Mad Scientists in the purest sense, with oft-retro aesthetics ranging from Raygun Gothic to Victorian-esque Steampunk. The Virtual Adepts are technomantic computer hackers with Urban rebel Cyberpunk flair, doing in the real world what Neo did in The Matrix. And of course there is the Technocracy, which has lots of gadgeteer genius engineers of their own, especially among Iteration X; the difference being that the Technocracy encourage a mass-producible, utilitarian type of gadgeteering, while the Etherites use idiosyncratic gadgets that may or may not work for others, and the Adepts fall somewhere in between.
One tribe of werewolves, the Glass Walkers, in Werewolf: The Apocalypse has adapted to modern times and learned to use their spirit magic to talk to the spirits of machinery and urban landscapes.
The Nockers from Changeling The Dreaming are changelings whose fairy souls are drawn to technology, although their curse means every gadget they build will have some sort of hidden flaw, which sometimes results in explosions; the evil counterparts of the Nockers are called Gremlins, who in their Fairy self look nothing like the creatures in the movies of the same name but more like small pointy-eared people with green skin and sharp pointy teeth... and they grin a lot, especially when they've just planted a booby-trap somewhere or sabotaged a piece of technology.
Nockers are also capable of scaring a piece of machinery into working temporarily by cussing at it.
Werewolf: The Forsaken has the Iron Masters, who tend to stay close to humanity and urban habitats. They have an affinity for Technology Gifts that, at the highest level, allow them to make a technological device out of the base materials (that is, a circuit-board out of plastic and sand).
Mage: The Awakening has the Free Council, modernist mages whose studies lead them to explore magic through a humanistic lens, drawing on human art, culture, science and technology — the last of which often results in SCIENCE!!!
Changeling: The Lost has the Wizened, who were kept as caretakers, craftsmen, and busybodies for the True Fae. They have an affinity with Contracts of Artifice that allow them to manipulate and construct (or deconstruct) machinery; the top level of one set allows them to make a hovercraft out of a go-kart and an inflatable raft. And due to the fact that ANY changeling can purchase Contracts of Artifice like the Wizened (it's just more difficult for others) virtually any changeling can be a Gadgeteer Genius as well.
And then there's the fanline Genius The Transgression, where most of the player characters are these, capable of making inventions that bend the laws of physics to the breaking point. Powerful Geniuses are easily the most effective at gadgeteering; whipping up an entire fleet of spaceships is possible.
The Mad Scientists in Deadlands are similar to the Wild Cards series example above; the devices they make barely work on their own, if at all. The power behind their science-breaking steampunkness is evil spirits the characters are unwittingly channeling. Well, not Hellstromme, he knows exactly what he's doing.
The Artificer base class from the Eberron campaign setting of Dungeons & Dragons is a magical version of the Gadgeteer Genius.
GURPS has two levels of this. Gageteers can build things that break the laws of physics if they have lots of funding. Quick Gageteers can do the same thing in half the time with rubberbands and cheese.
In Warhammer Fantasy the Skavens clan Skyre is a group of giant rats numbering hundreds of thousands if not millions of Gadgeteer Geniuses. The engineers of the empire follows this trope quite good as well. The dwarfs might at first appear like this but their constructions aren't that improbable and most are old engines based on experience and new inventions are rare.
The Ork Mekboyz of Warhammer 40,000 might as well be gods of this trope, being able to construct Humongous Mecha out of a mound of scrap metal and a hot water heater. Not to mention every other piece of Ork technology from cars to guns to back scratchers are made in this way. Since this knowledge is bred into their DNA, and they aren't really that bright, they use latent psychic powers to cover up flaws.
And make Da Red Ones Go Fasta!
The supers game Godlike likewise has gadgeteers turn out to actually have nonsensical gadgets that only work because their "inventors" believe they do, most likely as a way to prevent a Reed Richards Is Useless situation.
Traveller: The Terran Confederation is this in Intersteller Wars. When they first meet the Vilani they are thousands of years behind. However they surpass them in less then two hundred years.
In Pokémon Live!, Giovanni built MechaMew2, a giant robot Mewtwo, all by himself.
His grandson, Mid, might represent this trope even more.
Cid Del Norte Marquez from Final Fantasy VI oddly enough doesn't work with Airships, but is no less of a Gadgeteer Genius seeing as he invented Magitek and designs Powered Armor, weapons, and even pseudo-genetic engineering.
However, if you go out of your way to visit the crashed Blackjack after Terra and Locke leave Vector on the way to the Crescent Island, you can find Cid on board offering to help Setzer repair it, claiming he has some prior experience with airships. Setzer politely turns him down.
Cid Kramer of Final Fantasy VIII put up part of the money used to rebuild the mass people mover that would eventually become Balamb Garden (The rest comes from The Mafia, which causes problems later on), which functions as the party's primary mode of transportation early in the story, and negotiates with a city of engineers to help actually create it to his specifications.
It's easily overlooked given who he is, but Scooter qualifies. To quote Angel: "He may be missing a few chromosomes, but he's a savant when it comes to vehicles." Ellie, Scooter's sister, also qualifies as well.
Many of the Asura race from Guild Wars qualify, but especially Zojja from the 2nd game.
The whole of the Engineer class focuses on the use of inventive gadgets to fit multiple situations- you quickly forget that you're limited to pistols, rifles and shields as conventional weapons when you start using flamethrowers, turrets, grenades bombs and wrenches as class-specific weapon kits.
Billy Blaze, alias Commander Keen, from id Software's Commander Keen series. Commander Keen built a spaceship in his garden, made from old soup cans, a joystick, a car battery, a vacuum cleaner and a bottle of Everclear.
Lucca in Chrono Trigger. She resides in a kingdom with a mostly medieval aesthetic (though they do have refrigerators, at least), yet she is able to build a fully functioning teleporter, and when the party comes across a robot from the year 2300 she has little trouble fixing him up.
Jeff Andonuts of EarthBound. He's capable of using laser guns, bombs and the like, and can turn various broken irons, antennas, harmonicas, and the like into powerful weapons and battle items overnight. And did we mention that he's only thirteen years old?
Ciel from Mega Man Zero. And the two above examples seem like amateurs compared to her. Her accomplishments? Creating a perfect replica of X (Cain certainly couldn't, partially why mavericks exist), she created an energy system to solve the energy crisis that is not only effective but just beautiful (take a look at the reactor of the Guardian airship from ZX!), and she made Biometals to match Master Albert's, but also added the dual Mega-Merge feature. And she created Copy-X when she was nine years old. Don't believe me? Read the MegaManZero Complete Works.
Area from Street Fighter ex2 plus. While they didn't give her much of a story, they did say that she was a greater inventor than her father.
The Engineer of Team Fortress 2 is capable of creating NASA-level sentry turrets and teleportation devices using nothing more than his wrench and scrap metal collected from weapons dropped by the recently dead.
Don't forget his laws-of-thermodynamics-be-damned dispenser, and the fact that he can make one from scratch using the raw metal of a butterfly knife. Which he invented. In the 60s. Then again, he does have 11 PHDs, so it's a little justified.
Butterfly knife be damned; that man can make a physics defying dispenser out of a wooden baseball bat.
This trope is the defining characteristic of both Gnomes (Alliance) and Goblins (Horde) in World of Warcraft. Gnomish tinkerers are famous for inventing bizarre (if not reality warping) inventions including (but not limited to) helicopters, robot chickens, teleporters, mind control helmets and even world shrinkers. Goblins on the other hand tend love explosives of all kinds and are masters bombmakers, rocketeers, and sappers; but also make lumber harvesting robots, airships, and motorcycles. Players of any race can take the "Engineering" profession, which allows them to embody this trope, but Gnomes have a racial bonus to Engineering (Goblins have a racial bonus to Alchemy). The profession even allows the player to create Mad Scientist style goggles and to make unique modifcations to their armor such as parachute cloaks and rocket boots.
Gnomes and Goblins, although generally on opposite factions, have a friendly rivalry and often cooperate on complex engineering tasks and love to compete in racing.
Although true to Gnomish and Goblin tradition, player made inventions have a nasty tendency to backfire through explosions, accidental size modification, poultryfication, and teleporting you far above the ground. If it does not do any of this it is either a bomb, has a massive cooldown time, or is a robot or something that works once before breaking.
Another gnome from a completely different universe/game (and a definite case of Our Gnomes Are Weirder), Jan Jansen from Baldur's Gate 2 starts the game with a crossbow (including bolts), gloves, boots, and goggles of his own design, most of which give him a big bonus to his thieving skills. Originally, he would have invented more gadgets as the game went on, but this was sadly scrapped due to lack of development time.
Grubb from Septerra Core. He built several robots of different types out of rubbish thrown down from Terra 1.
Deus Diablo in The Nameless Mod; he built an inanimate object with the powers of a board admin, something Gamespy couldn't do, hence why he was kidnapped.
Edgar from Final Fantasy VI designed many of the machines used and exported by his kingdom, including the weapons he uses in battle, most infamously his giant chainsaw. His Job class is described as "Machinist" and, where everyone else is wielding swords, knives, or staffs, Edgar is the only one holding a huge gun.
Bill from Pokemon Red And Blue, who invented the storage system, as well as his colleagues who helped him. In the manga, he also invented the Vs. Seeker.
This trait also seems to be the hat of most electric type gym leaders. With the exception of Elesa due to being a model, Lt. Surge, Watson, Volkner, and Clemont have had a huge hand in setting up the complex design mechanisms for their gyms for one reason or another.
Carl, your chief engineer in MechWarrior 4 has a reputation as one. The saying goes "Give Carl a hundred tons of steel wool and he'll knit you an Atlas overnight."
Professor E. Gadd from the Super Mario Bros. series. Also, Shy Guys, who count as Gadgeteer Genius Mooks. Luigi also becomes this as Mr. L.
The steampunk RPG Arcanum allows players to be gadgeteer geniuses, eventually building such things as steam-powered robots, staffs that shoot lightning and a device that can revive the dead.
The whole Bui bui species from Loco Roco series. To lesser extent, Mui mui too.
Rika fits this even better; She managed to build, arm, and pilot at least three separate tanks designs in a setting devoid of the industrial grade machinery usually required to construct one.
The Gadgeteer is an actual class in Wizardry 8, and it's just as powerful as you'd expect. Thankfully the rarity of components means that you can't really have more than one in the party, which keeps the game from becoming unbalanced.
Gadgeteering exists as a power set in the MMORPG Champions Online. One of the abilities being an 'Experimental Ray' which has a chance for various effects, including turning the target into a teddy bear.
The Gadgeteer is also the name of a class in Twilight Heroes - they make many of the gadgets and devices that they use in combat.
Puck of Vanguard Bandits is capable of repairing the strongest and oldest ATACs in record time and can keep them in working order with the smallest of resources. Taken to extreme levels as he proves he is fully capable of making an ATAC even stronger than the one legends portrayed as strongest using only scrape parts of a broken machine and a weaker power source. Takes a dark twist at the end of the "Ruin" path when he improves Zulwarn's efficiency. It only needs a few drops of blood instead of a mass human sacrifice to power it, though it still corrupts people.
Victoria Van Bathysphere from LittleBigPlanet 2. The later portion of her level is an Eternal Engine and she made a robot army.
Eagle Eye Mysteries: Word Of God says that Jennifer Eagle's character was created specifically for her to be this. In-game, she built the Eagle Eye Detective Agency's TRAVIS hand-held computer, and is rather picky about who gets to wield it (only Eagle Eye members have the privilege).
Solatorobo has Merveille, who is credited with single-handedly raising the bar for Kurvasz Mini-Mecha design. She's also quite skilled in biology, Creating Life while barely old enough to be out of high school. The shopkeeper Suzette and Red's sister Chocolat are both Wrench Wenches.
The Lombaxes from Ratchet & Clank are an entire race of Gadgeteer Geniuses. Ratchet himself was able to build a functioning space ship out of A BOX OF SCRAPS! spare parts IN A CAVE! on Veldin simply by following Gadgetron's voice prompts (not to mention the list of his wacky inventions that Clank rattled off), and the Lombax Secret is in fact an inter-dimensional portal device. According to the Smuggler, Lombaxes can't leave any invention the way they found it and are forever tinkering.
Captain Syrup in Wario Land II. All the boss fights against her involve knocking her out of various hovering vehicles that sport various weapons, and one fight sees her remotely controlling a robotic Spear Man.
Amanda Ripley of Alien: Isolation at one point manages to repair a motion tracker unit using parts from a children's toy. She also crafts her own medkits, explosives and electronic decoys from random gubbins and scrap metal parts she finds lying around the station.
In Barbie: Life in the Dreamhouse, Ken tries to help Barbie by making such inventions as a Master Computer to index all the clothes and accessories in her Unlimited Wardrobe, and a Shrink Ray to keep her countless trophies and awards from flooding the trophy room. Skipper also proves herself a competent inventor when she "Skipperizes" Barbie's boutique with new makeover machines.
Yes you do! If you haven't seen Vanamonde von Mekkhan's description of this coffee , you will find the need to find the Foglios and have them tell you how they came to our universe so we can go there and get some. The only downside is you'll never be able to fully enjoy other cups of coffee again.
Kat from Gunnerkrigg Court builds an antigravity generator out of a thermos and coat hangers for the school Science Fair. She doesn't see this as anything special, and builds it simply to grow experimental protein crystals properly. Much to her chagrin, nobody cares very much about proteins, but are fascinated by her anti-grav machine.
Signs: Protein is Great!
Student: Wow! Zero Gravity!
Later, she converts it into a personal aircraft.
Tedd from El Goonish Shive is a male version of this trope. Grace, the squirrel-girl girlfriend of Tedd, has her moments as well.
It later turned out she is actually one-fourth of a biocomputergestalt, she is a lot more competent when she's with her "sisters"
Though they do have a disturbing tendency to make things that explode... including bug nets and self-motivated slinkies. That explode.
In The Adventures of Dr. McNinja, Sean "Dark Smoke Puncher" McNinja, the brother of Dr. McNinja, is shown to be particularly technologically adept and his own brother noted that his own Mecha-Mooks are more dangerous than normal.
Not to mention Annarchy, especially in the Rain Slick Precipice of Darkness games where she upgrades your weapons and builds a Humongous Mecha to defeat a Physical God. Also meets the female and school-age requirements.
Dr Nonami stars a young female scientist who invents a variety of machines to fight evil.
Doc and Roger from The Whiteboard tend towards this, triply so (at the very least) if alcohol is involved. Notable inventions include a fusion-powered paintball gun capable of firing through time, and a micro air compressor which runs on nitroglycerine as petrol isn't powerful enough.
Voodoo Walrus has a "house badger" by the name of Professor Kaboodles who has seemingly evolved in the background from being a simple pet badger to a full on goggle and lab coat wearing inventor. Though no one notices. Even when he's shooting lasers at floating pygmy cows.
Walter from Dubious Company, regularly upgrades the ships he steals with complex Magitek, and is the go-to-guy for Techno Babble. His first on panel instance of this is in the shipwrecked arc, where he built a fully-furnished house in the course of an afternoon without tools. It was also a Visual Gag about his animal instincts.
The various gadgeteers (follows the laws of physics) and devisors (considers them more of a guideline) of the Whateley Universe have this as their mutant talent. Ironically, Word Of God has canonically stated that even they can't actually make a giant robot that works. Not that this keeps the relevant perpetual school project nicknamed "Tiny Tim" from having its own Crowning Moment of Awesome during the Halloween battle...
Jobe Wilkins' father is a gadgeteer genius villain. He resents Jobe for being a bio-devisor instead of a gadgeteer like him.
Makes-Things, Techno-Dann, in Protectors of the Plot Continuum. Technically, anyone who works for the Department of Sufficiently Advanced Technology can qualify.
The Web Serial NovelThe Descendants has a lot of these: Codex, Tink, and (at least in the backstory) Chaos all serve this role, as do many of the villains—most notably Maven.
A staple villain type in Super Stories, usually with their own, restricted specialty. Veldron is a whiz at electronic circuitry, Clockwork is brilliant with medium-scale engineering such as, well, clockwork, and Devnull is a programming and hacking genius.
There's also the Masks universe, where this is one of the mutant powers, besides for instance Bricks (really tough and strong) and Flyers.
This is a super-power in the Global Guardians PBEM Universe. Some Gadgeteer Geniuses have only the power to make one very, very advanced device (Roland Jaffe created an iPod-sized battery that could store more electricity than a ten-foot-high pile of car batteries, and Peter Dansker, a technician for Lucent, built a truly sentient android over the course of a weekend), while others are able to toss out new technology as easily as they can breathe.
In the web novels Trinton Chronicles there are two characters who fit this, one is Robert who took actual schooling on robotics and the other is Brandon who's super power actually allows him to understand machines.
Essay (hero), Gimble (neutral) and Triton (villain) are notable examples in the Academy of Super Heroes universe. Gimble is notable because she makes physics-violating tech that everyone can use — even Anchors.
In Worm, parahumans with the power to instinctively visualize and understand how to put together advanced technological devices are called Tinkers. It is unclear as to whether everything a Tinker makes follows the laws of physics or can be mass-produced by normal people, although some Tinker-made tech seems to be in widespread use. Some are more competent than others (Leet can build any type of device only once, and the closer an invention is to something he's made before, the more likely it is to misfire.) Other tinkers specialize in certain fields of technology (Bakuda makes various kinds of bombs, Bonesaw works with biological organisms). Dragon, who mainly builds suits of powered armor, has the reputation of being the most powerful and skilled tinker in Worm's universe, though it actually turns out that she is an extremely advanced AI who was built by a now-deceased tinker, and is able to design things through her advanced intelligence.
It is revealed that Tinkers are actually tapping into the knowledge of the entities that grant them their powers, and as those entities have visited- and destroyed- countless other planets in the past, they have access to advanced technologies devised by alien civilizations. In some cases, they also have a subconscious ability to scan their surroundings and determine how the recorded information can be applied to Earth-specific situations.
The main character of LegionOfNothing, Nick, is a Gadgeteer Genius with his own suit of Powered Armour, with which he fights crime as a superhero called "The Rocket". He's helped by having access to the work of his deceased grandfather, who was also a Gadgeteer Genius. While their work can be replicated by ordinary people, it's a lot more advanced than normal technology. It's unconfirmed whether this is an actual superpower or just natural intelligence.
In Brennus, this trope is the superpower of "Gadgeteers" such as the main character. While never impossible, Gadgeteer technology is decades or even centuries more advanced than normal technology, making it a very useful power to have.
Penny in Caper built what is essentially the Iron Man suit. She then stole it from the Tony Stark expy, who had funded it.
In "Caelum Lex" Cyrus Soliveré and Adrasteia Atelier, both engineers from a young age, consistently override security protocols, wrangle together engine pieces and build any gadget needed for a specific mission.
Dr. Heinz Doofenshmirtz. Despite being a normally Harmless Villain, he is capable of building -inators that are as impressive as the inventions of the title characters.
Also, the Fireside Girls, led by Isabella. They're usually just helping the boys out, which is impressive in itself, but they can build a Time Machine.
Jimmy Neutron is only a kid, but he has already surpassed any known scientist in capablity. Each episode focuses on one of his invention although his inventions usually fall pray to Flowers for Algernon Syndrome.
They make holographic projectors out of steam engines and lasers out of a flashlight, a piece of wood, and a bottle!
If you're looking for a person example, Numbuh 2 would be the man. You just have to get past his Punny way of life.
Edd from Ed, Edd n Eddy. He makes an industrial-grade excavator out of junk he found around his neighborhood.
Professor Von Slickstein of Inspector Gadget, who even incorporated gadgets into the title character's body.
The Inspector's niece and dog, Penny and Brain, are the more competent gadgeteers, though they are just as likely to become the Damsel in Distress (both of them are subject) or Wrongly Accused (Brain, while simultaneously being the Damsel sometimes) while Gadget plays the Spanner in the Works.
In addition to commentary, Stone Cold Steve Austin provided this service in the original run of Celebrity Deathmatch. His technological expertise yielded a fully-functional cloning machine (used to combine DNA from dead celebrites into fighting mutants) and a rickety time machine (used to bring to life such matches as The Three Tenors vs. The Three Stooges).
Gear from Static Shock, who initially thought his power was rather lame: "How am I supposed to fight supervillains, think them into submission? All I can be is your Mega-Mechanic." Which turns out to be a great way to fight supervillains.
Jack and Maddie Fenton in Danny Phantom seem to fit this trope, with their inventions being proven inoperable by a normal person, or even The Guys In White, due to the quirks because of said "tin cans and an old transistor radio" method of construction.
Professor Utonium from The Powerpuff Girls creates things like a supersuit or a giant robot or a car that can turn into a giant robot.
Jérémie from Code Lyoko. His gadgeteering occurs more in the virtual world, however, as he is the primary programmer and the one who is most adept at using the Supercomputer. However, it is a confirmed fact that he can build robots, participating in a robot competition in Season 1. He also created an EMP bomb in episode "Ultimatum," which has efficiently stunned a XANAfied person at this occasion.* Wade from Kim Possible is able to build more or less anything that the plot demands. And the Tweebs that were able to really pimp Kim's car. The three of them are 10 years old...
On the villainous side, Motor Ed is a mechanical genius. Seriously!
Tanya from The Mighty Ducks is introduced as "She was so smart, she actually knew how to program a timer on a VCR!" As well as building the team's machines and blowing up those of the enemy, she used a wrist mounted chainsaw in battle. She also had a stutter due to her brain going so fast (and trying to explain things in terms the others could understand).
Tinkerbell is one of these in her origin story movie. This actually comes from the original J. M. Barrie's Peter Pan: She mended pots and kettles, at least. The name really does come from her being a tinkerer.
Grumpy from Adventures in Care-a-Lot straddles the line between this and Bungling Inventor. He apparently built an entire theme park at one point, not to mention a cloning device, among many others, but his inventions sometimes turn on him (i.e. the clone cloned itself and both clones kicked him out for not being "Grumpy" enough) or fail because of (unwanted) help from Oopsy.
The Geek from Sam & Max: Freelance Police fits the original mold perfectly, as a young genius girl who built a gigantic robot Max in her underground lair.
Rattrap in Beast Machines was stripped of all weapons upon being reformatted, so compensated by developing all sorts of handy devices to stop the Vehicons.
Similar to Fred's modification of the Mystery Machine, Alan of The Amazing Chan and the Chan Clan programmed the iconic Chan Van to be able to transform into just about anything. Even a dynamite truck.
Loonatics Unleashed: Tech E. Coyote manages to cobble together a model of the city in his spare time. This model comes complete with trains that actually run on time. When not in his spare time, he makes the heroes' arsenal.
Wheeljack, from Transformers. He created the Aerialbots and the Dinobots, and while some of his inventions don't quite work out in the explode-y sense.. his fuel pump is in the right place. He also invented lots of useful things. Like the Immobilizer, which worked great until it blew up, and the Negavator, which worked great until it blew up, and that bomb, which was supposed to blow up, so it definitely worked great.
Razor from SWAT Kats is the primary force behind the eponymous duo's technology (though T-Bone occasionally demonstrates that he's no slouch at least when it comes to engines), and thus they made military salvage into a working supersonic jet that's armed to the teeth with all kinds of unique missiles. His knowledge has limits, however, demonstrated in the last episode when he despaired over fixing a broken radar jammer.
Tennie from Motorcity. She even built the home she and her father live in. Jacob is this as well, having invented the Utility Bots. Also Dutch.
Strudel from The Hub'sPound Puppies tends to make her inventions from discarded items and the occasional more sophisticated electronics she comes across.
Tobey from WordGirl is a 10 year old kid who, in his spare time, builds giant robots to do his bidding.
Sun Jifa, a 51-year-old Chinese farmer, built himself a pair of working prosthetic arms out of nothing but scrap metal after losing his old ones while making a BOMB to go blast fishing with.
The book The Boy Who Harnessed The Wind is about a real-life example of this. William Kamkwamba, a fourteen-year-old Malawian boy, was forced to drop out of school because his family could no longer afford the tuition. Using some books from a foreign-aid funded library and parts from a scrapyard, he constructed a fully functional windmill to run appliances in his family's home, largely creating the design from scratch.
Wolfgang von Kempelen was a real life example from the 18th century, known for creating, among other things, a speaking machine and a chess playing 'automaton'. The later required an operator sitting inside and controlling the puppet through an elaborate mechanism, and using several other mechanisms to conceal himself when the machine is opened up, creating the illusion that the whole structure is fully mechanical.
Wu Yulu is a 46-year old farmer from a rural area of China near Beijing. While he has very little in the way of formal education, he has over the past thirty years built over 26 robots to do everything from light cigarettes, to scale walls, to drive rickshaws, building them out of scrap metal. In true Mad Scientist tradition, he nearly drove his wife to divorce, plunged them both into tremendous debt, destroyed his home and scalded his face with acid. All For Science!! Or at least his crazy hobby.