Stomach of Holding

Some people and creatures can use their stomach to keep stuff within, sometimes more than would comfortably fit in there. (Of course, it helps if they can gag it all back up when necessary.) Handy and unlikely to be found by frisking, if quite disgusting.

The acidic action of digestive juices rarely come into play.

See also Swallow the Key. Compare Treasure Chest Cavity.

Anime and Manga

 * The first of the Maniwani Ninjas from Katanagatari seemed to specialize in this.
 * In Cowboy Bebop, Spike does this. He swallows a cigarette when told there's no smoking in that area, then burps it up later. He repeats the process with a poker chip in the same episode.
 * Bleach: Dondochakka Birstanne
 * In the Fullmetal Alchemist second anime and manga, Kimblee stored a Philosopher's stone either in his stomach or his mouth when he was in prison (though probably not at all times).
 * It's implied he's kept two at once in his stomach on occasion.
 * Gluttony has an entire dimension in there. However, it isn't filled with digestive juices - it's filled with an ocean of human blood.
 * Naruto has several examples:
 * Orochimaru stores his sword, Kusanagi, inside his throat in reference to the Kusanagi of Japanese mythology which came from Orochi's body.
 * When giving a report on the enemy, Kisame coughed up a scroll with the information on it before giving it to a summon shark.
 * Kinkaku is shown to store a special sword and fan inside of his stomach.
 * Possibly Gerotora entering the seal for the 9-tails by having Naruto swallow him whole (with some assistance) and/or Itachi having him swallow a crow
 * Tsuyu, a My Hero Academia character, has this as one of her abilities. She considers it gross.

Film
"Dr. Amusa: Couldn't you have just...kept swallowing it? Greenberg: [queasily]...no."
 * In The Incredible Hulk, Bruce swallows a USB drive just before one of General Ross's attacks makes him Hulk Out. Later, after he's reverted to normal, we hear him in the bathroom of the motel "retrieving" the device, shall we say.
 * In The Hot Rock, during the gang's attempt to rob the diamond for their client Dr. Amusa, member Greenberg swallows it before he's caught by the guards. During a brief stint in a city jail, it passes through his system and he stows it in the cell, now out of their reach.

Live Action TV

 * In the Star Trek: Deep Space Nine episode "Who Mourns for Morn?", it is revealed that he kept the latinum — removed from the gold in which it's normally stored — in his second stomach, which is why all his hair fell out.

Oral Tradition

 * In the Hungarian folktale "The Little Rooster and the Turkish Sultan", the rooster has a magic stomach like this, which he uses to great effect: he can swallow and regurgitate everything from a well's entire water supply to a swarm of hornets. And since this is a children's tale, he does the latter without killing the insects; instead, he uses them as a Groin Attack Breath Weapon against the Sultan - no, we're not making this up!

Tabletop Games

 * Dungeons & Dragons: Second Edition Dark Nagas can swallow objects to spit out later, using a bag-like internal organ to carry things. The organ has thick, rubbery walls that protect the naga against pointed and sharp objects, protect the cargo against digestive juices and prevent magic items in the cargo from being detected.
 * There is also an inversion — an item that looks like a bag of holding but actually leads to the maw of an extra-dimensional creature.
 * This is one of many possible powers for a chaos familiar which an evil wizard in Warhammer Fantasy Battle can obtain.

Video Games

 * Kirby has this in Squeak Squad, allowing him to store various powers or recovery items, among others.
 * Final Fantasy: The Fat Chocobo first does this in III and does it again in IV.
 * This was where Tomba's inventory was located, he even was able to keep live animals in there.
 * Klaymen of The Neverhood stores items in a cabinet-like space in his torso, complete with a door.
 * In Metal Gear Solid, Solid Snake smuggles a pack of cigarettes to use on his mission. When asked about how he managed to do that (considering he's been thoroughly searched prior to his departure), he replies: "In my stomach." Justified in that he explains he could only do this because he was given a shot that suppressed his stomach acid.

Web Comics

 * Ace Dick, from Problem Sleuth, can use his stomach as an additional inventory slot (and even has a "stomach capacity" statistic that rises as he levels up).
 * Schlock Mercenary: Sergeant Schlock tends to store his plasgun in there.

Web Original

 * The SCP Foundation gives us a strain of the flu that allows you to regurgitate anything useful at the moment. The items take mass from your body and there are mutations that result in either harmful substances or different exit points.

Western Animation

 * Ed, Edd 'n' Eddy: Ed's apparently works like a storage facility or refrigerator sometimes.
 * Chowder often stores things in his stomach. Even things that could not possibly fit there.
 * Rico from The Penguins of Madagascar. As well as 'small' things like lit dynamite, bombs, bowling pins, and a running chainsaw, it is also revealed that he has an elevator and a spiral staircase for getting to the bottom. His stomach can safely hold Mort too.
 * In "Roger Dodger", Roger the Aligator switches minds with Rico. Roger keeps coughing up dynamite and flamethrowers, showing that it's an ability of Rico's body, not of his mind, but only Rico can control what comes up.
 * The title character of Bounty Hamster has Cheekpouches of Holding.
 * Family Guy: Mayor Adam West keeps everything he needs in case he is ever held hostage in his stomach, such as an inflatable raft for escape purposes and a magazine for him to read in case his escape fails. He also has Stratego in case anyone wants to play.
 * Most humanoid robots in Futurama have a hollow torso with a door that makes for a handy storage compartment.
 * In an episode of South Park, the boys are trapped in a cave after a cave-in. Cartman finds a huge stash of buried treasure, and over the course of a few days, swallows it all in order to smuggle it out without the other boys knowing. He ends up a grossly misshapen human sack of treasure until he can't hold it in anymore and craps it all out at the end of the episode, after which the cave was revealed to have been an old tourist attraction, with the treasure being fake and made out of plastic.
 * In an episode of Jimmy Two-Shoes, Jimmy coughs up a surfboard almost as big as he is.
 * In a Powerpuff Girls episode, Junior of The Amoeba Boys produced paper clips, a flashlight, and a basketball from his stomach.
 * On a few occasions in Animaniacs Yakko and Dot have retrieved things from Wakko's stomach.
 * In Batman the Brave And The Bold, Plastic Man is able to do this, presumably because his body is plastic and thus not as damaged by swallowing a bunch of gold coins. And it's usually gold coins he's swallowing.

Real Life

 * Drug runners who swallow tightly wrapped packets of cocaine or heroin to get them past customs, with a real risk of the packets rupturing and killing the runner with a massive overdose.
 * At the South African diamond mines workers are regularly X-rayed before leaving.