Adored by the Network: As of April 2020, British satelite channel Sky Cinema Disney is obsessed with airing this movie alongside Toy Story 4 and Mulan. On Easter 2020, it played twice (once in the morning and again in the evening), and it aired another time during the overnight hours.
Baby Name Trend Starter: The year before the movie was released, the name of the film's protagonist, Riley, was the 32nd most popular baby name for girls in the United States. After the film's release, the name jumped 20 places up on the chart to become the 12th most popular girl's name, and then became the 7th most popular baby name in 2016 after it was released to DVD and Blu-ray. In 2020, the name jumped to 3rd place, likely because of the launch of Disney+ boosting the film's popularity.
Beam Me Up, Scotty!: Bing Bong does not say "Take her to the moon for me, Joy." He actually says: "Take her to the moon for me, okay?".
Children Voicing Children: Rejected soundclips of Mary Gibbs' voice from Monsters, Inc., which were recorded when she was three or four, are used for any unintelligable sounds Riley makes during scenes featuring her as a toddler. Most notably, one of Boo's squeals from the door chase scene was used for the flashback of Riley crying over an ice cream cone. The lines spoken in the sequence following the introduction of Riley's personality islands were also provided by an actual child whose name is unknown.
Latin America: Intensa mente (literally "Intense-Mind", but it's a pun where the suffix -mente is used on adverbs. When combined as one word, it's literally "Intensely", but it could be interpreted as "Fiercely" or "Passionately").
Spain: Del revés ("Reverse").
Portugal and Brazil: Divertida Mente ("Fun Mind"; like with Latin America case, as one word means "Amusingly").
Russia: Головоломка (figuratively, "Puzzle" or literally, "Brain Breaker").
Quebec: Sens Dessus Dessous ("Topsy-Turvy").
Japan : インサイド・ヘッド ("Inside Head").
Israel: הקול בראש ("The Voice in the Head", but also a homophone of "It's All in Your Mind").
Germany: Alles Steht Kopf (literally "Everything's on its head", figuratively "Topsy-Turvy").
Polish: W głowie się nie mieści (Literally "Head can't contain it", but it's also an idiom for "unbelievable" or "inconceivable").
Danish: Inderst Inde (roughly "Deep Inside", but "inderst" refers to the very deepest you can go. The term is often used as an idiom for the core of your personality).
Taiwanese Chinese: 腦筋急轉彎 ("Riddles").
Cantonese: 玩轉腦朋友 (Literally "Fun with Brain Friends", but a pun is used here as "Brain" 腦 is pronounced the same as "Old" 老).
Vietnamese: Những mảnh ghép cảm xúc ("Puzzle pieces/Fragments of Emotions", but with "fragments" meaning "parts of a whole" instead of "broken pieces").
Two ad-libbed lines by Bill Hader and Mindy Kaling were of Fear declaring his love to Disgust ("I've always loved you!" "Ugh, I know."), but they weren't included as it distracted from the story.
Distanced from Current Events: On March 22nd, 2016, Starz Kidz played a 2:00AM encore airing of a broadcast that had happened 5 hours prior. Right when it got to the part where Joy and Bing Bong fall in the memory dump, the Brussels attacks began. This caused Starz to limit airings of this movie across their networks.
In Memoriam: The film ends with the dedication to the memory of Brian Smits, who was a software engineer at Pixar.
Method Acting: Kaitlyn Dias (Riley) revealed in an interview that while recording the scenes where Riley is crying, she was also crying as well in the recording studio. She would imagine her cat, May, dying to trigger an authentic emotional response.
One-Book Author: Yuko Takeuchi's only role in an animated work was voicing Joy in the Japanese dub.
A good number of people have been introduced to Boston's "More Than a Feeling" thanks to the second trailer.
The same thing, to far lesser extent, with Aerosmith's "Sweet Emotion".
Spread My Wings is more a case of "Introduction By Commercialization" - the song was virtually unknown before being used in some of the trailers, including the first part of the trailer mentioned above.
Troubled Production: Aside from the pressure of being Pixar's first attempt to get them out of theirDork Agenote which was light compared to the Dork Ages from classic Disney animation and DreamWorks Animation, the latter of whom was faltering in the middle of one in the new 10's, which applied more pressure for Pixar to come through for the industry , the unique concept meant twice as much time spent on development. Production design alone lasted five years, the longest for designer Ralph Eggelston, and the emotions' distinct "grainy" surface texture was almost dropped because it was too difficult and expensive for just one character, let alone five. Towards the end of it, Pete Docter was seconds away from a nervous breakdown and quitting.
Word of God: Pete Doctor has confirmed that Riley having both male and female emotions does not mean the character was conceived as being gender fluid. He claims that the only reason the emotions are mixed-gender is because it was funny to him.
Write Who You Know: Riley and her experiences are based on Pete Docter's own daughter Elie (who played young Ellie in his last movie) and how, as soon as she reached age 11, went from being giggly and playful to quiet and introverted. According to Pete Docter, she did enjoy the film and found it touching.
According to Word of God, Joy is 4'2 in relation to the environment of the Mind World. If she was scaled to an equal size in the human world (or, conversely, Riley in Headquarters as in the earliest idea), there's a chance that Riley would be One Head Taller than her, depending on how tall Riley actually is. Though in one of the film's earliest drafts Joy was small enough to sit on Riley's shoulder when she (Joy) did go "inside out".