Don't Touch It, You Idiot!

""If you put a large switch in some cave somewhere, with a sign on it saying 'End-of-the-World Switch. PLEASE DO NOT TOUCH', the paint wouldn't even have time to dry.""

- Thief of Time

Another one of the Genre Savvy's Stock Phrases. Just like how there are some things nobody is absolutely ever supposed to say, there are some objects the viewer/reader can instantly, instinctively tell nobody is ever supposed to touch: the singular artifact placed on a pedestal in the abandoned Temple of Doom, the Mineral MacGuffin locked in a treasure chest buried in a cave on an uncharted island, the glowing MacGuffin in a display case in the Diabolical Mastermind's study, or the Forbidden Fruit surrounded by signs that boldly warn DO NOT TOUCH! WILL CAUSE THE END OF THE WORLD AS WE KNOW IT!

Who Would Be Stupid Enough to touch any of that? Fortunately for the plot, plenty of Genre Blind characters are, all the while ignoring their Genre Savvy companion's warning of "Don't touch it, you idiot!" They never listen to them. Cue the rolling boulder/erupting volcano/invasion of Mooks/release of the Sealed Evil in A Can and all their complications.

In his analysis of the Fairy Tale, The Morphology of the Folktale, Vladimir Propp concluded that the functions "probihition" and "disobedience" really formed a single plot function; any prohibition was bound to be violated.

This Trope is for variations of a warning Stock Phrase by the Genre Savvy. Otherwise, see Forbidden Fruit and Schmuck Bait (of which the Big Red Button labeled "DO NOT TOUCH" is a Sub Trope). Plus, if someone ever asks, "What does this button do?", this is the only acceptable way to answer.

Anime and Manga

 * In an Azumanga Daioh Yonkoma, Tomo relates a dream to Yomi where she saw a Big Red Button she just had to push. Then Chiyo ran in and pleaded for her not to push it, because she (Chiyo) would die. Naturally, Tomo pushed it, and Chiyo died.
 * Similarly, Tomo (awake this time) saw a freshly-painted wall with a "Do Not Touch!" sign. She smacked her hand on it, to Yomi's irritation.
 * When they visit Chiyo's summer home for the second time, she remarks how bad it would be if they lost her key to the house right before getting inside by unlocking it. Cue Tomo grabbing the key and throwing it into the grassy area surrounding the house. Needless to say, no one is amused, and when they do find the key, Sakaki is called on to physically restrain Tomo.
 * Which was probably necessary, since Tomo just had to blurt out how amusing it would be if she found the key and instantly threw it away again.
 * In One Piece, Spandam is given the special Transponder Snail to trigger the near-apocalyptic Buster Call, and brandishes it, and gloats about it, and uses it to manipulate Nico Robin...and then presses it by accident. Whoops.
 * Those Telesnails really have it in for him. After he accidentally triggers the Buster Call, he also accidentally activates his regular Transponder Snail so that everybody on the island can hear his ensuing conversation with Nico Robin in which he claims it's perfectly okay if all Navy troops die as long as he can capture her and get away with his skin intact. They are not amused.
 * In an episode of FLCL, the mayor's daughter finds Naota, the main character, unconscious with cat ears on his head. She reaches out to touch them, and is then interrupted by Haruko yelling "DON'T TOUCH IT!" into a megaphone. They then have a conversation, with the girl touching the ears and seemingly nothing happening... until she clutches her stomach and passes out. The scene ends with Haruko saying, "I told you not to touch it. Is that my fault?"

Comics

 * A short comic in Nodwick Lampshades this, in which Yeagar pull a sword from a stone, which is surrounded by signs saying "Don't be a jerk! Leave it alone!", "You toucha dis sword, we break you face!", and so on. Drawing the sword is supposed to result in many, many misfortunes (most of which are ridiculous and hilarious), though none of these actually seem to come to pass.
 * Putting the sword back in is apparently just as dangerous.

Film
"Evelyn: Come on, no harm ever came from opening a chest.
 * Subverted in Coraline, where she flips the switch BEFORE seeing the "Do Not Flip" sign. What she thought was a light switch, was actually the electricity in the room that her dad's computer was in... while he was still using it.
 * A subversion occurs in the James Bond movie Goldeneye; during his talk-through of all of the gadgets he'll be using on his next assignment, James finds and picks up a good-sized sub sandwich. Q sees this and immediately grabs the sub out of his hands, telling him not to touch it... then explain to a bewildered Bond that, rather than a hidden gadget of mass destruction, it's his lunch.
 * As I recall, Bond was only half-listening (as usual) to Q's explanation about a pen-grenade while picking up said sandwich. The look on Bond's face when Q grabbed the sub out of Bond's hands was pretty funny: he looked like he thought he'd actually picked up another grenade.
 * In Pans Labyrinth, after being told by the faun under no uncertain terms not to eat ANY of the food in the Pale Man's room, that her very life depended on it, and brushing away the frantic warnings of the fairies, Ophelia takes two grapes from the banquet table and awakens a child-eating monster who bites the heads off two of the fairies and nearly gets her.
 * Of course, the point was supposed to show how Opfelia did not blindly obey orders and thus was the opposite of her fascist step-father. Unfortunately, it came across as making her look rather Genre Blind (worked a lot better when she disobeyed the fairies and opened the door they weren't pointing at).
 * Who would be crazy enough to stay in the presence of the Pale Man any longer than necessary, anyway?
 * Van Helsing: "If there's one thing I've learned, it's never be the first to stick your hand into a viscous material."
 * Time Bandits: "Mum! Dad! It's evil! Don't touch it!"
 * The Mummy: "NOOOOOOO!! YOU MUST NOT READ FROM THE BOOK!"
 * Evelyn apparently does not learn from the past; in The Mummy Returns, when they find a chest locked in a ancient Egyptian safe:

Rick: Yeah right, and no harm ever came from reading a book. You remember how that one went?

Thirty seconds later a wall crashes in and the Nile floods the room."


 * Men in Black: Agent K tells Agent J not to touch anything. What does Agent J do? Touches a small ball thing. Cue destruction and mayhem.
 * An Ironic Echo echo occurs in Men in Black II, Agent J pretty much cries this when Agent K, having been neuralized from previous film, touches a small round object, which turns out to be a tiny planet.
 * Aliens: "Nobody touch nothing."
 * The Lord of the Rings: While the gang is deep in the mines of Moria, Pippin the Hobbit innocently fiddles with an ancient suit of armour... Gandalf reacts appropriately.
 * And then there's the Palantir.
 * And Wormtongue examining the gunpowder with a lit torch in his hand, which Saruman quickly guides away.
 * Though nothing comes of it, Ash says almost exactly this line to his medieval love interest Sheila in Army of Darkness when she tries to examine the mechanical gauntlet he's building. Ash goes on to chastise her with "your primitive intellect wouldn't understand alloys and compositions and... things with molecular structure," his voice trailing off as it becomes clear that he doesn't really understand any of it either.
 * In The Brink's Job, while robbing a gumball factory one of the thieves notices a door with a sign that says DO NOT OPEN THIS DOOR. Hilarity Ensues.
 * The Emergency Stop lever on Spaceball One is labeled "NEVER USE".
 * In The Rocketeer, when Cliff and Peavey first discover the stolen rocket-pack hidden in an airplane in the hangar, Peavey is examining the pack while Cliff holds one of its ignitions buttons, making Peavey say "I wouldn't touch that if I were you...", but he does, making the rocket-pack fly around the hangar.
 * Inverted in Space Jam. Near the end of the film, Michael Jordan comes in with a basketball and asks his fellow top athletes to touch it, but they initially refuse to, thinking it's some sort of trap.
 * One of the protagonists in Film/Battleship is warned not to walk on and touch the giant mysterious floating structure.

Literature
""Go away. This is not a place to be. If you do try to enter here, you will fail and also be cursed. If somehow you succeed, then do not complain that you entered unwarned, nor bother us with you deathbed prayers." Signed, "The Gods.""
 * Harry Potter: Harry's companions ask him what in blazes he thinks he's doing when he reaches for a glass orb on display above an inscription that includes his name in the Department of Mysteries. Harry actually picks it up, fully hoping that something dangerous or at least exciting will happen to make their excursion there worthwhile. Be Careful What You Wish For...
 * Of course, he learns from his mistakes enough to know not to stick his hand blindly into Dumbledore's Pensive in Goblet of Fire. Such a shame he managed to accidentally touch it by leaning in too far.
 * The Magician's Nephew: Polly tries to tell Digory how ridiculous it is to want to ring the bell just because a sign dares you to ring it, but Digory just has to find out what happens. He releases the Sealed Evil in A Can.
 * In the Heart of Gold Arthur Dent sees a button labelled "Do not press this button." Upon pressing it, a sign lights up reading "Do not press this button again."
 * In Roger Zelazny's Lord of Light, the demons are bound in a vault the door of which is inscribed with the words:


 * Played with in Patricia Wrede's Dealing With Dragons. The character who is only identified as the stone prince knows he has to use the tin dipper, not the one made of solid gold and covered in jewels, to take the Water of Healing from the well. But he figures it can't hurt to just have a look at the gold one, right? Wrong, but at least he was Genre Savvy enough to do something better than panic as he watched himself become petrified, resulting in a seriously subverted Taken for Granite situation.
 * This trope shows up often in Discworld, especially with the wizards.
 * In fact, at one point Ridcully had to put up another sign to specifically deter other wizards, which in effect says "No, don't do it even to see what would happen".
 * And even then somebody did.
 * In fairness, though, it wasn't a wizard, and it wasn't done to see what would happen. It was done because it was the only way to get the cheese tray to the wizards...
 * In the Chronicles of Prydain series, there are at least two major artifacts (and several minor ones) that can cause painful injury, or even instant death, if the wrong people try to handle or use them. The sword Dyrnwyn is the most plot-central example; the inscription on its hilt, visible above the sheath, begins: "Draw Dyrnwyn, only thou of royal blood." Taran, who grew up on a farm but doesn't know his true heritage, tries to draw it anyway, and his companion all but quotes the page title warning him not to.
 * Sranul. Frequently bordering with Too Dumb to Live and Tempting Fate.
 * This is about Alther's reaction to Jenna touching the time-travelling Glass in Septimus Heap. Needless to say, she does touch it, falls into it and ends up in a time 500 years before.

Live Action TV
"JACKSON: New guy!
 * The Goodies plays with this in the very first episode, as the Crown Jewels have a sign placed by them reading "Please Do Not Steal". It doesn't do much good.
 * Many episodes of Are You Afraid of the Dark, e.g., "The Tale of the Mummy's Curse," when the daughter of a museum curator finds a secret compartment in a mummy's coffin. As she reaches to open it, her brother tells her, "Don't touch it! There's a curse!" She finds a potion and ring that grant immortality, accidentally raising the mummy back to life.
 * In one episode of That 70s Show, Eric is jealous of the attention his father Red gives to Hyde, and resolves to do something stupid to get Red to notice him. Kelso immediately suggests bouncing a bowling ball off the living room couch to see what would happen. Hyde insistently tries to warn Eric against doing this, but Eric refuses to listen. Of course, the bowling ball bounces off the couch and smashes through Red's TV set. Eric gets some attention from his father, all right...but not exactly the kind he was looking for.
 * Later in the episode he even kicks himself for thinking anything Kelso said was a good idea.
 * Hiro in Heroes immediately goes to open the safe his dead dad (in a Video Will) told him never to open. Inside is the formula he's not supposed to touch, and another video from dead dad saying, "I TOLD YOU NOT TO TOUCH THAT!" Sadly, even that second reminder doesn't get Hiro to put the thing away before someone steals it.
 * Kelly in Dead Set repeatedly tells people in the house "don't touch the doors" because there are zombies outside.
 * Played for laughs in an episode of Babylon Five, where Garibaldi is shown into his guest quarters and told not to touch anything. He immediately begins touching everything in the room, saying "Touch! Touch!" aloud.
 * Doctor Who. The last words we hear in "The Face of Evil" is the Doctor shouting at Leela not to touch that button after she's slipped inside the TARDIS. Cue the latter dematerialising, and the Doctor now has a new companion.
 * Even earlier, in "The Daleks' Master Plan", he tells Katarina "NO! NOT THAT!" regarding a certain switch or button... which opens an air lock.
 * "Don't. Touch. The Baby." - which Rose then does, of course. (At least it was by thoughtless instinct, not by intentional disobedience or due to curiosity as a character flaw.) This leads to the Doctor actually dying in that time line.
 * Stargate SG-1 season 9 has the newly reformed SG-1 enter a dormant laboratory used by Anubis for unknown purposes. Colonel Mitchell starts pushing buttons looking for the light switch, whereupon Dr Jackson forcefully informs him that while he may be the CO, he's also the new guy and should now stand in the corner while the grown-ups work.

MITCHELL: Hey! You touched that...

JACKSON: I know how to read that."

"Multiple voices: And NEVER return to a familiar place prior to the last time you left."
 * In an episode of Burn Notice, Michael narrowly averts Better Manhandle the Murder Weapon by saying this to someone who was about to do so.
 * Farscape: the ancients' relatives give John a very VERY strict warning about wormhole travel:


 * Cue John returning to Earth over a decade before he left. * Face Palm*
 * In Canada's Worst Driver, host Andrew Younghusband told a guy not to turn the ignition switch because the vehicle was already running. Said contestant did two or three times.
 * In Lost in Space, Dr. Smith made a constant habit of touching alien artifacts and devices even after being warned that it was a bad idea. This never worked out well.

Mythology

 * The sequence from the Aladdin animated movie below is, in fact, taken from a genuine version of the original tale, although in that version Aladdin follows the advice. Good thing he did, too; in the original version he was told that he'd die instantly if he touched the walls. Maybe actually being told what would happen is what saved Aladdin from what happened to so many other victims of this trope... plus, if he died there, it'd be a pretty short story.
 * Moreover, a number of European folk tales follow the same pattern; there is one about dogs with gigantic eyes and a snuffbox that would summon them to act as genies. In all of these tales, the protagonist follows the prohibition, though in some cases he may accidentally brush an item with his clothing and trigger disaster.
 * This is a staple of fairy tales. It usually falls into two categories: The good vs. evil sibling stories and the husband and wife stories. In the former, the good child/sibling is told not to do or touch something and obeys while the wicked child/sibling does not and suffers some form of punishment. In the husband and wife stories, the protagonist (either the husband or the wife) finds a spouse through magical means and is given some sort of order, like not to hit them with iron or to sit on a rock without moving. The order is inevitably ignored or disobeyed, causing said magical spouse to be forced to leave the protagonist. In some fairy tales, the spouse is gone for good, but in others they are found again after several years of searching and trials. This kind of fairy tale goes way back to the myth of Psyche and Eros, when she was told not to look at her husband when he came to her at night.
 * There's the story of Pandora's Box, which released all kinds of evils and diseases into the world. She knew something bad would happen if she opened it, but she did it anyway.
 * Depending on the telling, Zeus set up the box as Schmuck Bait to punish mankind for accepting fire from Prometheus.
 * Depending on how one interprets the story, the box could represent gaining sapience, having to face knowledge of all the world's ills instead of simply existing as animals.
 * Some versions specifically say that Zeus gifted her with strong curiosity to ensure that she did open it. If the Olympians were determined to see something happen, chances are they'd get their way.
 * Yet another version says that there was no box at all. Just Pandora - the first human woman even created that Gods dumped on a previously single-gender human world as a punishment for stealing Gods' fire. Women ...
 * There's also the forbidden fruit of Adam and Eve. As with the Greek mythology example above, it could be an allegory for mankind gaining sentience, but is often instead treated as a cautionary tale of disobeying God.

Newspaper Comics

 * This Dilbert comic.
 * Also this one.

Tabletop Games

 * At least two separate pieces of fluff text in Warhammer 40000 books list "Don't touch tha-" as the last words of a Sergeant or squad leader regarding Tyranid Spore Mines.
 * The Tomb of Horrors actually relies on this. Amongst other things, the rod that will kill you if you do it, the trap that will kill you if you stick your hand in, the three chests that are ALL trapped... Really, don't touch the whole module and go play something else.
 * Every D&D adventuring party can recall the party member who died by trying on the cursed armor (usually over the rest of the group's protests.)
 * Or having to make a hasty retreat because someone touched a load-bearing floating rock.

Video Games
"Tyrael: Fool! You have just ensured the doom of this world. You cannot begin to comprehend what has been set in motion this day. Go to the Temple of Light in the city of Kurast. There you will find the gate to Hell open before you. You must find the courage to step through that gate, Marius! Take the stone to the Hellforge where it will be destroyed. Now run... Grab the stone and run!!"
 * The original Space Quest featured a button marked "This button is not to be pushed at any time" in the escape pod. Pressing it caused the player to wind up in King's Quest I where the pod would plummet straight into a moat filled with hungry alligators.
 * In the VGA remake the scene was changed to the pod winding up in Conquests of the Longbow instead, and would simply crash and burn against a hillside.
 * I suppose that in the matter of intent this wouldn't fall under this trope, but Shadow's.... special cry of 'DON'T TOUCH IT!' in Sonic the Hedgehog 2006 just begs to be mentioned here.
 * For those wondering, the boss quickly snatches the Chaos Emerald.
 * In Modern Warfare, there is a credits sequence which takes place in a museum. The museum contains scenes from the game, with statues that move when you get close. There is also a big red bell that reads 'Do NOT press this button'. Pressing it results in every statue coming to life and attacking you.
 * There's an item in Shadow Madness called Pandora's Box, the item description of which recommends the player to save before using..
 * In one of the Thief games, there's a "Do Not Press" red button inside a butcher's shop in a warehouse district. Pushing it release a giant spider to attack you.
 * There's another one several missions later, presumably for those who missed the first and/or the terminally slow on the uptake. This one releases SEVERAL giant spiders.
 * The Ulduar raid in World of Warcraft features a large button labeled "DO NOT PUSH THIS BUTTON". Pushing it causes the nearby boss, Mimiron, to yell at you ("Didn't you read the sign that says 'do not push this button'?"). It also activates Mimiron's hard-mode encounter, which involves the room you're in starting to explode, as well as the classic "This room will self-destruct in X minutes" warnings over the loudspeaker.
 * The button in the pool in Maniac Mansion, though of course you know that most everyone pushed it, despite the warning anyways.
 * In Lost Vikings 2, one of the Vikings pushes a button labelled "Do Not Touch", thinking it read "Donut". This launches them across time and space, forcing them to have another quest to find their way home.
 * Marius finds himself venturing into the tomb of Tal Rasha alongside the Dark Wanderer, eventually finding the shackled mage in the flesh. Before the Dark Wanderer can release him, Tyrael involves himself and the two duke it out. Marius approaches (under the belief Tal Rasha wants to be released from his miserable fate), only for Tyrael to call out to him not to do it. Marius doesn't listen.

"Buck: "...had to go and touch it.""
 * In a somewhat inverted example (in that when you place a sign, people will generally do the opposite), in Minecraft online servers, if you put up a sign on your house that says "Do not grief", chances are, you will be one of the first ones to be targeted for griefing. Of course, if you're dumb enough to believe that posting a sign would actually convince a griefer to not grief your house, you probably somewhat deserve it.
 * In a straight example, many death traps have a sign that says "Do not push this button" or "Do not try to steal from this treasure chest." Guess what people do?
 * Buck from Wildstar says this to HIMSELF in the cinematic trailer when he accidentally activates something in a broken-down giant robot, unleashing a swarm of killer drones.

Web Comics

 * Order of the Stick: Castle Self-Destruct. (Do not touch ever.) (No, not even then.)
 * Dan and Mabs Furry Adventures "Remember. Always idiot-proof your lab!"
 * Touch! Touch! Poke! Touch!
 * Played straight in this Good Times strip.
 * Saves A Fox from Goblins repeatedly tells everyone not to touch anything in her quasi dungeon crawl with Grem, K'Selliss and Dies Horribly. Naturally, everyone else keeps doing it anyway. Eventually this frustrates Saves so much that she begins angrily screaming she doesn't care anymore, they can touch whatever they want, she's going to save her breath. This only encourages K'Seliss to touch her...
 * This also gets K'Seliss in trouble later when he rips the finger off an undead abomination, intending to eat it.
 * "DON'T TOUCH!!" "NO" "CAN YOU READ?"
 * In Wapsi Square, Bud warned Monica that she shouldn't touch an artifact because it had frightened a group of Nazis enough to make them kill each other. Naturally, Monica touched it, but not before Tempting Fate. Bud was Genre Savvy enough to expect this, and had even taken bets on whether or not Monica would touch it.
 * Played with in Exterminatus Now: The Mad Scientist Laboratory has a Big Red Button for the Self-Destruct Mechanism labeled "Do Not Push". Of course, the Mobian Inquisition wants to destroy the base, so they push the button. It turns out that.

Web Original
"PLEASE DO NOT STRIKE GONG
 * Referenced and lampshaded several times in Ursula Verson's The Book Of The Gear series. The explorers of the labyrinthe, self-modifying and seemingly boundless structure known as Gearworld find that it contains many hazards, several of which are marked by polite signs left by an unknown group calling themselves the Monks of Perdition. These signs always take the Forbidden Fruit factor into account and plead the reader to heed them while acknowledging that they may very well choose not to do so. The uncovering first such sign can be found here:

While we fully understand that you are curious as to what happens when the gong is struck, we must strongly advise against it. The results are most unpleasant and dramatically fatal. Human nature being what it is, we realize that this warning may not stop you, and may in fact only drive you to strike it, but since we are unable to destroy the gong, and the lock was evidently insufficient to keep you out, we can only hope that you will take our advice. There are neither riches nor knowledge here, but only an ugly death.

Respectfully,

The Monks of Perdition

In Memory of Brother Wu"

"Bulma's father : Make sure not to touch anything, like the gravity control. Or the start button.
 * The emailed-around Don't Press The Red Button thingy.
 * Dragon Ball Abridged:


 * Show the button*

Bulma's father : The start button. Don't touch...THE start button. Now I'll be right back.

Goku : Okiedokie.


 * 3 seconds later* Goku : Wonder if this is the button. * Shuttle blast off in space*"

"Serenity: Ponies! I love ponies!
 * Red vs. Blue's resident Genre Savvy chararacter Church, upon discovering that "the stupidest being in the universe" will be responsible for a prophesied apocalypse, attempts to warn the team ditz, Caboose: "Don't touch anything, don't look at anything, don't breathe on anything!" By then, though, it's already too late.
 * Yu-Gi-Oh the Abridged Series had a variation of this, where a magic door appears in front of Serenity, Duke and Tristan, telling them to open it. When Duke asks what's behind the door, it answers "You will enter a world of deep, unending pain and torment! ...Oh, and, uh...ponies." The following dialogue actually happens twice:

Duke: Serenity, NO!


 * opens the door*"

Western Animation
"Aang: Well, don't touch it!
 * Avatar: The Last Airbender: Aang and Zuko find "some kind of mystical gemstone" in the Temple of Doom in "The Firebending Masters," and Zuko goes right for it.

Zuko: Why not?

Aang: Remember what happened out there with those spikes? I'm just very suspicious of giant, glowing gems sitting on pedestals."

"Aang: You had to pick up the glowing egg, didn't you?"
 * To make a short story shorter,

"Iroh: "Zhao, whatever you do to that spirit, I'll unleash on you ten-fold! Let it go now!""
 * Similarly, Iroh threatens Zhao not to hurt the moon spirit. When he does it anyway

"Homer: "Mmm...forbidden doughnut...""
 * In The Legend of Zelda cartoon, Link tells Zelda not to touch the Armos statues while they explore a labyrinth. Guess what Zelda does while asking "Why?". In the ensuing battle, she accidentally touches another and Link is thrown into touching a third.
 * Disney's Aladdin: Aladdin is told to "touch nothing but the lamp" when he enters the Cave of Wonders, and is successful in following this bit of advice (except for touching the magic carpet, which was apparently permissible). His monkey sidekick Abu, however, doesn't have the self-control that his master does, and it results in the two of them having to make a daring escape as the Cave of Wonders collapses around them.
 * Perhaps the carpet wasn't part of the cave of wonders, and was left there by someone who didn't want to risk touching the ground (but failed anyway).
 * Or the carpet doesn't count as a "thing" since, being sentient, is technically a person.
 * DON'T TOUCH IT!!! It's the History Eraser Button, you fool!!!
 * Though to be fair, Stimpy was put in charge so he would be tempted to touch the button that would wipe them out from past and present. Ren just didn't expect Stimpy to actually do it.
 * In the Disney film The Sword in The Stone, the owl Archimedes warns young Arthur not to touch the titular sword, especially since choral voices and beams of light appear when he does. Arthur, of course, ignores the warning and pulls out the sword anyway. And is promptly crowned king.
 * The Simpsons - Homer's sold his soul to the Devil for a doughnut - but he's smart enough to know if he doesn't eat it all the Devil doesn't get his soul. So later that night, as he's rummaging through the fridge, among lots of tasty goodies there's a chunk of doughnut with a big sign attached - "HOMER'S SOUL DOUGHNUT - DO NOT EAT". Of course, since Homer is half-asleep, and even at the best of times isn't too bright, he eats it anyway.

"Bart: I know I shouldn't...but when am I gonna be here again?"
 * In another Halloween episode, when Bart is running from vampires, he sees a switch labeled "Super Happy Fun Slide". Despite knowing it would turn the stairs into a slide and send him right to the vampires, he pulled it anyway. His reasoning?

"Frylock: Will you just throw that damn thing away? If you keep it around here you're gonna eat it and then you're gonna die!"
 * In the Arthur episode "Arthur's Big Hit", D.W. stupidly broke Arthur's model plane. He worked on it for days and told her a million times "Don't touch it!" Breaking which Arthur hits her arm, yelling, "I TOLD YOU... NOT TO TOUCH IT!"
 * Don't touch anything.
 * Aqua Teen Hunger Force - Frylock spends the entire episode chastising Shake this way in the episode The Broodwich.

"Batman: Listen, and listen good. You don't touch anything, say anything, or do anything unless I tell you! Got it?
 * The Out of the Inkwell cartoon "Koko's Earth Control" has Koko the Klown and his dog Fitz enter the control room for the planet Earth, and Fitz's attention turns to a lever marked "Danger/Beware - If this handle is pulled, the world will come to an end." Naturally, despite Koko's attempts to stop him, Fitz pulls the lever, and although we don't see the world end as such, things do get really crazy.
 * Used in the Gummi Bears episode "He Who Laughs Last" where "Don't Touch It, You Idiot!" becomes "Don't Eat It You Idiot".  Made even worse when Zummi lost his medallion, which was needed to reopen the Great Book and find the spell to save Tummi.
 * The Batman the Animated Series episode, "Harlequinade" has a very funny one after Harley Quinn wants to listen to the Batmobile's radio and presses a button that instead expels the Batmobile's parachute.

Harley(small voice):Yes, sir."

"Doomsday Door: Do Not Open Until Doomsday!"
 * In the first episode of The Real Ghostbusters, construction workers digging more tunnels for the New York subway system come across a door with a demonic face that repeatedly telling them to not open it until Doomsday. Because they're on a schedule, and because they don't want to be told what to do by a talking door, they attempt to continue digging. And when the door sees that they aren't going to listen to it, it then opens, unleashing Hell On Earth into New York's subway system.

Real Life

 * British artist Damien Hirst has spoken of an exhibition he will never be allowed to do. It consists of a big red button with DO NOT PRESS written under it. When people (inevitably) ignore the sign and press the button, a boxing glove shoots out and punches them in the face.
 * The 'DO NOT TOUCH' art exhibit in the Science Museum in London comes close: a bare metal pole surrounded by yellow and black warning stripes and large signs warning people not to touch it, as they will get an electric shock.
 * There is much debate over what kind of warnings to put at nuclear waste burial sites that might actually keep future generations (or aliens) away, rather than simply tickling their curiosity (assuming proper documentation of what's actually there has fallen by the wayside). One suggested possibility is to start a But Thou Must Not religion, the idea being that religion is a way of keeping a message going for a really, really long time. Well, something vaguely recognizable as the message, anyway.
 * See Sealed Evil in A Can for how well this can end.
 * Animals in nature that are painted bright shiny colors so that animals know "I'm horribly poisonous; don't eat me!" Pretty sure they still get eaten. And the consumers die.
 * Many brightly colored animals, like Monarch butterflies, simply make predators sick, which still protects other members of the species without relieving any pressure on competing species.
 * Poison ivy, hot pots and pans without an oven mitt, wet paint... Real Life is full of things like this.
 * "Tell someone there are a million stars in the sky and they will believe you. Tell them the paint is wet and they will have to touch it to be sure."

Other

 * In the Evil Overlord List, one of the items is that all devices will have a well concealed self destruct button, and an obvious button labeled "do not press" which will trigger an immediate spray of bullets into anyone stupid enough to disregard it.
 * The Indiana Jones and the Temple of the Forbidden Eye attraction at Disneyland revolves around a recently-discovered temple where an ancient deity resides, offering to bestow upon visitors endless wealth, eternal youth, or visions of the future, on the one condition that they don't look into the deity's eyes. If they do, they'll be led to certain doom. Almost as soon as the ride starts, the vehicles enter the treasure room, which contains a large statue of the deity's face on the far wall ... and you can guess what happens from there.
 * Of course, there is also the rope you're not supposed to pull.

Don't click here, I'm warning you!