Speaking of Achievement Hunter, if Michael Jones offers you a taco, you take the taco. Or else, he and the rest of the crew will take your desk and everything on it. Just ask Chad.
At the conclusion of the Mechakara arc in Atop the Fourth Wall, Dr. Insano captures the crippled Mechakara and tortures him with a magnet. Why? The robot made Insano cut his hair.
Speaking of Mechakara, the only reason he murdered his universe's version of Linkara and skinned him so he could use magical devices and started a Robot War to Kill All Humans...was because he thought Linkara's voice was annoying and he wanted him to shut up.
The infamous Navy Seal Copypasta, in which a man claiming to be a Navy SEAL, expert in gorilla warfare, and sniper with over 300 confirmed kills announces his intention to trace the other person's IP through a spy network and then murder them—in response to a minor online insult.
In Peach's Revenge, after Bowser successfully manages to kill Mario, Peach makes it her mission in life to destroy everything that he holds dear, starting with burning his Koopaling henchmen alive.
Ice the Frosty Cat utterly destroyed Ranger in the most humiliating way he possibly could in game 10 of Comic Fury Werewolf... for something Ranger did in Game 6—catch that Ice was a werewolf. Keep in mind, by that point, Ranger had died in game 6, so Ice didn't lose because of Ranger.
In the web series Beebo, Harry shoots his titular cat in the face for smoking weed. Admittedly, he had warned that he would do so if he ever caught him smoking again after the first time it occurred, but it was still disproportionate nonetheless.
Criticized: Arthur Lements kidnaps and tortures Darian Stonehall because he gave his film a negative review that was so viscous that every film studio ended up rejecting it. He threatens to kill Darian along with his wife and son if he fails to write a new positive review of the film. He later assaults Darian again after the retraction review simply because he gave the film 3.5 stars out of 4.
In the very first episode of Da Amazin OT Advenchr, The Bully calls Lite a "fgt". Two episodes later, Lite kills him and another person who called him a "fgt".
The SWAG leader of Demo Reel assumes that kidnapping someone at gunpoint and leaving them to starve to death slowly in an abandoned patch of woods is justifiable punishment for his territory getting threatened.
In Dragon Ball Z Abridged when Frieza asks Gohan and Krillin what planet they come from Krillin almost tells him out of fear but Gohan stops him... only for Dende to do it out of revenge for Krillin constantly calling him Little Green.
Echo Rose: The "Fallen Angels" responded to Echo claiming that they were being mean to other students by making up a lie to get her fired from her job as school janitor.
In the Youtube video "Muppet Sex Tape", after Kermit catches Elmo shamelessly flirting with Miss Piggy, he tells him that if he catches Elmo leaving a voice mail to Miss Piggy again, or if he ever sees them together, he will have Oscar thr Grouch break his kneecaps and then get Bert and Ernie to rape him.
Go Animate videos where a person is Grounded will invoke this trope heavily. It doesn't matter how minor the offense is, expect the person being punished by being grounded for an impossibly long time. This is the start, though - many videos have shown the target being expelled from school for getting a math problem wrong, toys destroyed for playing sick and even outright killed.
The machinima series Hard Justice is all about a police force that dishes these out to people. Got your music on too loud? Turn it down or you'll get a rocket to the face... point blank. Of course, it's all part of the Big Bad's plan to have the most ineffective law enforcement possible so his criminal actions goes unnoticed and unpunished.
"If you ever, ever break my orders again... as God as my witness I will devote whatever time I have out of jail to making your lives living Hells. I will break your knees. I will beat up your wives and kids. I will make fun of your mothers and kill your fucking pets in front of your eyes. My wrath will be as extensive as it will be disproportionate, because I have no. Fucking. Sense. Of perspective. Do you idiots hear me?"
The Insanity Wolf Image Macro sometimes depicts extreme acts of revenge on petty things. Here are some examples:12◊ 3◊
This gets discussed without a hint of irony in the Jayuzumi video "Baby Crying Trolling". After the titular noise keeps playing and understandably annoys the teens in the lobby, many of the players say they want to smack the baby really hard or outright kill it. Of course, since this is the internet we're talking about it's unlikely they'd actually go through with it.
In the "The Golden Sins Of Horror Games" episode of The Jimquisition, Jimsaw has put Phillip Spengler of Microsoft's X-Box division in an ironic deathtrap, wherein he has to walk barefoot across a bed of razor-sharp broken Doritos to get a key to free himself from a device that will drown him in Mountain Dew, because his company has created and encouraged a culture of corporate thralldom and rampant, mindless consumerism. Cliff Blezinski is behind the real trap, having given Jimsaw all the tools he needed to create the deathtrap to get him to lay a bed of razor-sharp broken Doritos between himself and freedom, all because he gave Gears of War 3 an 8 out of 10 rating.
In Bacon Flavoured Thoughts! by Matt Santoro, Matt says that disliking bacon should be punishable by death.
This basically Master Zen's arc in Noob. He ended up in jail and hence lost his command of the Noob guild due to his own Hair-Trigger Temper (though he blames it on the guildmate whose act of idiocy caused him to commit Accidental Murder in real life). When he escapes and wants the guild command back, everyone prefers Arthéon's command over his. As retaliation, he kindaps Arthéon's player in the webseries version, attempts to kill Omega Zell and Sparadrap's players in the comic version and frames Gaea for the act that causes Fantöm to be permanently deleted, turning their whole faction against them in all versions of the story.
In "Toad's Mistake 3", Toad eats some Sara Lee Cheesecake, a dish that Shrekeats constantly. Shrek chases him while holding a knife, gives him a swirly, craps on him, and murders him in a blender.
Principal Steinbeck once gave Toad a violent beating all over a paper ball.
In "Black Yoshi's Job", when Black Yoshi has to babysit Bowser Junior, he pulls out his gun and shoots Junior's toys when Junior makes him play with one tiny dinosaur against his many bigger ones. He also threatens to pull out his gun again when Junior won't let him play with his Thomas the Tank Engine toy, and even shoots Toad when they play doctor.
In "Black Yoshi's Call of Duty: Black Ops III!", when Mario buys Black Yoshi a Call of Duty: Black Ops 3Wii U bundlenote which does not exist in real life and was created solely for the video instead of the PS4 bundle, Black Yoshi destroys the Wii U by shooting it with a crossbow and threatens to kill Mario if he doesn't get him the PS4 bundle.
In "Jeffy's Mistake!", both Jeffy and Black Yoshi fell victim to this. The former destroyed the latter's Xbox One by tossing it out a three-story window after dying in a game of Grand Theft Auto, and the latter tied up the former and stuffed a grenade in his mouth for doing so.
In a youtube video called "Singing Session with The Great Samuel" the titular Samuel forces two people (Nitrotech and Solaris respectively) to sing under the threat of their steam getting hacked.
In the same video, Samuel says this to Solaris:
Slam Jam Sam:Solaris, you shut the fuck up while Nitro is singing. If I hear you cutting Nitrotech while he's singing...I will fucking kill you.
The Weather: Alan claimed his little brother tattled on him. When asked what he did about it, his caller said he'd have tossed his brother out on the street- which was apparently still too lenient for Alan, as he chose to drown his brother.
In the Whateley Universe, this is pretty much standard practice, which can't be too surprising, given that most of the stories involve several hundred emotionally-overcharged teen superbeings, many of whom believe Violence Really Is the Answer.
Overclock plotted to cause Tennyo to kill all her friends and be driven insane. Her crime? She ate the last of his favorite cereal in the cafeteria one morning.
Martial arts is one of the standard Physical Education classes at Whateley Academy. Counterpoint (power mimic with awesome powers and centuries of experience as a fighter) spars against Jobe (ordinary baseline powers but a genius with bio-weapons). Jobe wins by fighting dirty, but what happens on the mat stays on the mat, right? Not with the god of disproportionate retribution, Counterpoint. He pummels Jobe mercilessly. Does Jobe tell the authorities? No, he retaliates with his own disproportionate retribution by dropping a biowarfare weapon in their food. When Counterpoint recovers...
Strega's daughter is kidnapped by a secret society based in France. She then bombs the headquarters, captures Paris and holds the city hostage, and promises a invasion of Europe greater than World War II.
In Welcome to Night Vale, our Narrator Cecil gets so upset over the fact that his beloved Carlos had a haircut, that he reads out Telly the Barbers physical attributes and location, apparently hoping that a lynch-mob would form over that the hot, new guys hair being cut.
What treacherous barber should agree to such depravity? Who takes mere money, or even soulless joy, in depriving our small community of such a simple, but important, act as luridly admiring Carloss stunning coif?
In a later episode Telly is reported to have been seen living in the wastes outside town, giving haircuts to cacti and holding Carlos' hair in his hands and wailing at the sky, which Cecil considers a just fate. It is unclear if he was driven out, or if he came to realize the magnitude of his sin and exiled himself. Either is possible.
During Hole Diggers, Simon kills Duncan with his Atomic Disassembler for trying to continue with the golf course, even though it's not really possible or ideal.
During Shadow Of Israphel, Simon suffocates Strongman_Bruno in a tree, simply because he was cheated out of a strength contest.
After Kim Richards gets angry at Sjin for betraying her to Sips, he decides to make a sword specifically for killing her, naming it the "Kimslayer".
During Sips's Trouble in Terrorist Town series, Turpster commits RDM on a frequent basis, breaking the rules and eventually pressing Lewis Brindley's Berserk Button (video here), causing him to vow to kill Turps in the next round, irrespective of either's allegiance. What happens next is the Disproportionate Retribution. After he makes good on his threat and it turns out Turps was innocent, people understandably try to take him down. In the ensuing bloodbath, Lewis guns down Sips in self-defence, then fires on Trott unprovoked and kills him too before finally being taken down. Turps calls him out on this, and the Hypocritical Humour is lampshaded when Smiffy calls it "the worst case of RDM I have ever seen".
Sips: Lewis has been more effective than all the traitors combined this round.
The supervillain Accord's Super OCD is so strong that he wants to have a character executed for intruding on his meeting unannounced.
After Bakuda triggered, she held her university hostage with bombs for not giving her a perfect grade. Later, after the Undersiders beat her, her ego is so bruised that she carries out a bombing campaign against random Brockton Bay citizens, killing fifty people.
Oh hey, you put a regular axe through my car? Okay. I'll just spend my entire savings putting a giant axe through yourcar.
There's a video floating around of a girl who's supposedly pissed off that her boyfriend plays so many video games, so she takes his Xbox 360 outside and tries to bust it up with a golf club-tries being the operative word, because she has no idea how to swing the thing, so it really amounts more to gentle taps; her initial careless toss to the ground does more damage. Then comes the follow-up video, where the boyfriend objects to her mistreatment of his Xbox, so he takes her laptop and shows her how to really swing, demolishing the computer's screen in one blow.
SCP-2270 is a ritual used to summon the Mesopotamian god of war and the Sun, Nergal, to have him inflict Megaton Punch on whoever was targeted by a summoner. The Foundation discovered it after one person successfully performed a ritual against his target his annoying neighbor.
Vaguely Recalling JoJo: Forever gets pummeled senselessly by Star Platinum because he was being "suspicious" (walking up to the group while making grunting noises) in the eyes of Jotaro. Given that Forever wastes no time in appearing directly in front of the Joestar group and doesn't even try to attack them, it's possible that this version of Forever could've actually trying to help them.
There's a whole lot of it in Death Battle, thanks to the show's very premise. Sometimes, you'll get an actually understandable reason for the fighters to go at each other's throats, but others, you'll get stuff like Natsu trying to get Ace to pay his tab instead of dining and dashing and Master Roshi summoning Jiraiya's wrath by complaining that his erotic novels don't have any pictures in them, both of which result in - you guessed it - a battle to the death.
"Ravandil's Quest" plays on the common Warhammer lore of The Book of Grudges: a large formal record of those who have slighted dwarves in any way. Ravandil gets his name in the Book because he politely asked Urist to move aside on the road, and then when Urist not only refused, but began threatening him, Ravandil decided to just walk around him. Funnily, when Urist successfully kills him and Ravandil is returned to life, Urist bears no grudge whatsoever and treats him politely, suggesting that Urist really does consider "murdering someone" to be an equivalent exchange to a minor social faux pas.
Benrey: Hey man, I saw you at lunch earlier. You owe me... three dollars. Gordon: You have the three dollars? (Benrey aims his revolver at the clone) You're really gonna kill him over- you've killed for less, haven't you? (Beat) Benrey:Never mind, we're friends. (Bubby shoots him) Bubby: He owed me five!