The Zucker Brothers' classic movie Airplane is chock full of wack situations. And of course, said wackiness extends into the credits. Along side the credit for "Best Boy" is the credit for "Worst Boy." It goes to (who else) Adolph Hilter, who was objectively the worst.
In Ace Ventura Pet Detective (spoiler alert) Detective Einhorn tuns out to be a man. Who knew? The careful viewer did, because on Lieutenant Einhorn's desk is a carefully laid out fruit display consisting of a banana between two apples. Why else would you place fruit like that?
Time travel can effect the future. That's the whole thesis of Back to the Future. If you look closely enough, you'll notice that the Twin Pines Mall changes to the Lone Pine Mall after Marty hits one of the trees when he travels back into the past. There are consequences to your actions!
Did you notice the literal foreshadowing in Batman Returns? Before she turns into Catwoman, the filmmakers hint at who she will become. Michelle Pfeiffer is lit so that she has a Catwoman-like shadow on her face.
In Frozen, Kristoff states that all men eat their own boogers. This is clearly an ideology that the filmmakers disagree with. In the end credits of the film, they specifically make it a point to mention that they do not agree with this opinion!
I Am Legend came out in 2007, way before Batman vs. Superman ever happened. But since the film is set in the future (the future according to 2007, that is), the filmmakers had the foresight to include a movie poster for it. It's either smart marketing or someone has a crystal ball!
The Marauder's Map tells you where everyone is at Hogwarts at any given time. Which can lead to some very embarrassing reveals. Like the two sets of footprints of a couple "caught in the act" during the end credits of Harry Potter and the Prisoner of Azkaban. Hope they kept it safe!
The attention to detail in Hot Fuzz has spawned a plethora of internet essays. Angel gets stabbed in the hand by a Santa, then later you can see the scar from it when he's writing a letter. The stabbing Santa is played by none other than Peter Jackson.
In the "Lady in Red" scene of The Matrix, the filmmakers cast several pairs of real life identical twins to fill out the background. This was to give it the feel of "a repeating program." So, no, it's not a continuity error!
The car that is used to take people into the park in Jurassic Park is the same car that's used to take people out of the park in Jurassic World. You can tell, because they're both "Jeep 29." It's either that or they gave every single jeep in Jurassic Park the same number.
The carpet of Sid's room in Toy Story should look familiar. It's the same carpet of The Overlook Hotel in The Shining. You wouldn't think that this classic kids' movie is chock full of references to Stanley Kubrick's horror movie, but it is. Go figure!