Different in Every Episode

This doesn't even begin to cover the weird things that you will frequently see on the Middleton High sign.

If a Couch Gag is where something different shows up every time in the opening sequence, this is where something from the episode itself is always different. Not just the obvious story telling devices like characters, plot, and settings, (though it can play into them,) but rather more mundane things that are different just because they can be.

A subtrope of Running Gag.

May often overlap with Unlimited Wardrobe if most characters in the series are usually subjected to Limited Wardrobe, and one is different just because they can be.

Examples:

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    Anime And Manga 

    Comic Books 
  • Weird Pete's Games Pit in Knights of the Dinner Table has different signs (and occasionally graffiti) at each appearance. Some of the messages relate to the current plotline; others are stand-alone jokes.

    Literature 
  • Ms. Frizzle from The Magic School Bus will change her dress in every book to reflect the subject being covered.
  • Someone or something with the name "Shuttleworth" appears in nearly every Aunt Dimity book. Occasionally, it will be attached to a minor character with actual lines, such as Rev. and Mrs. Shutttleworth of Penford Harbour in Aunt Dimity and the Duke. It was also the name of an inn in Salisbury that Lori had once visited, and which she used as part of her cover story for Simon's visit to the hospital in Aunt Dimity Takes a Holiday. Most often, it is someone no longer on the scene due to death, or someone never seen yet referenced because they perform some plot function. Two of the references are from Finch (and possibly the same person), a Miss Shuttleworth once ran the village tea room, and Dimity names a Patricia Shuttleworth whose dog's unlikely victory in the local dog show caused a "kerfluffle". The same Shuttleworth (an art teacher in the nearby market town of Upper Deeping) is mentioned in Aunt Dimity and the Family Tree and 'Aunt Dimity and the Village Witch''. The name also appears on the tombstones of a family that died in an epidemic in Bluebird, Colorado; as one of Bill's clients whose demands keep him in London; as the pseudonym Sir Percy Pelham used to scout out Erinskil before his purchase of his island castle; and Mr. Barlow's Whitby informant on Prunella Hooper and Peggy Kitchen's secret son.

    Live Action Television 
  • Friends: The Magna Doodle in Chandler and Joey's apartment has a different picture each time.
  • The picture on Murphy Brown's Dartboard of Hate.
  • The funny message on Frank's trucker cap on 30 Rock.
  • The number on the whiteboard in Battlestar Galactica is a more-serious-than-usual example. It counts the population of the fleet and ticks down over the course of the series.
  • Police Squad! had a few:
    • Once an episode, Inspector Frank Drebin would visit Johnny the Shoeshine Guy for "the word on the street". After getting oddly detailed information from Johnny, Frank would leave and someone else would come, asking for (and receiving) advice specific to their line of work. This second person was different every episode—a heart surgeon, a theologian, Dick Clark, etc.
    • Any time Frank Drebin parked his car, he would hit another car or some garbage cans. With every episode, the number of garbage cans he hit at once would increase.
    • The opening credits of every episode would feature a different guest star. Who would invariably die before the credits ended.
    • The first episode parodied the practice of playing the end credits over a freeze frame, by leaving the cameras rolling while the actors just stand really still. Every subsequent episode introduces a different variation on this gag: the actors all freeze while a chimpanzee trashes up the office in the background; an arrested criminal notices that everyone else is frozen and tries to escape; the actors continue pouring a cup of coffee during the credits until the coffee mug overflows, etc.
  • The Price Is Right: Several pricing games during the Drew Carey-era have had these:
    • Cover Up: After Carey mentioned that the base "incorrect" price that had been shown at the start of the game didn't really have anything to do with gameplay, he began having the spaces used for running gags or something nonsensical. The first of these were pictures of Carey in different poses used for the portrait space on the $25,000 bill prop (used in Punch-A-Bunch); these have changed every time.
    • Punch-A-Bunch: After about 2009, Carey's portrait on the $25,000 dollar bill prop had him making funny faces and all sorts of other expressions, replacing the formal shot that had been seen previously.
  • One episode of The West Wing has CJ given a goldfish as a pet. It doesn't appear in every subsequent episode, but if Gail's bowl does make it into a shot it will include an ornament referencing that episode's plot.
  • In the same vein, there's the ornament in Dorothy's goldfish bowl in Elmo's World.
  • Fawlty Towers: most episodes started with a shot of the hotel sign on which letters would be skewed, missing, or humorously rearranged. Each week was different.
  • Malcolm in the Middle: The warning on Chad's shirt changes in every episode in which he appears.

    Webcomics 

    Web Original 
  • The Spoony Experiment: Spoony does most of his reviews just sitting in a green chair while you can see posters hanging on the walls in the room corner directly behind him. In pretty much every review he does, he changes those posters to reflect something relevant to the review itself, usually a movie poster or wallscroll of the movie or game he's reviewing. If it's anything Highlander related, it'll usually be a poster of that movie. Anything Japanese game related, expect to see wallscrolls of the game or of Cowboy Bebop: The Movie.
  • Similarly, The Angry Video Game Nerd would often switch up his background posters hoping people would spot the references.
  • The Cinema Snob is fond of doing this as well, though he tends to keep his Caligula poster at all times.

    Western Animation 
  • As seen by the trope image, the sign outside Middleton High on Kim Possible.
  • The sign outside Charles Darwin Middle School in My Gym Partner's a Monkey. Lampshaded when it says "This sign changes a lot."
  • The sign outside Peach Creek Jr. High in Ed, Edd n Eddy. The first time the school was shown (the Valentine's Day Episode) it referred to the school as Peach Creek High. That was probably an animation error, though.
  • The sign outside the pet shop in Fish Hooks.
  • The sign at the First Church of Springfield in The Simpsons, whenever it appears.
  • On The Weekenders, the pizza restaurant the characters visit to each week always has an outlandishly different theme; ranging from a Medievel Dungeon theme (where Pizza is 'tortured' into slices), a Spy Noir theme (where the Pizza is served in briefcases (and containing microfilm in the crust)) and even having a 'Clearance Sale' theme one time... for Pizza! Try and wrap your mind around that one.
    • There's also the museum that offers a sample of different exotic food in most episodes, as well as Tino's Mom's bizarre (yet apparently healthy) cooking.
  • The chief of The Secret Show changes his name every episode for security reasons.
  • Kimiko from Xiaolin Showdown has an Unlimited Wardrobe where she's always wearing a different outfit (and often hairstyle) in each episode simply because she can. Everyone else in the show is subject to a Limited Wardrobe, with a few special occasions as the plot of the episode demands.
  • On Bob's Burgers, the Burger of the Day that is posted on the wall changes every episode. It will also change during episodes that take place over multiple days.
    • Even the title sequence is different every episode, with the neighboring building accompanying a different business and the pest control van sporting a different livery.
  • In Squidbillies, Early Cuyler's hat says something different in every episode.
  • If the vet is involved, the animals that come and go in Martha Speaks
  • In Gravity Falls, Mabel wears a different sweater every episode, more if the episode takes place over several days.