The whole of the TV show ‘Lost’ took place in the mind of a goose.

Poltergeist II - At one point in the film Craig Nelson (aka the Dad) asks Will Sampson’s Medicine Man character if he’s escaped from a mental asylum. The way it’s played make it obviously a funny little nod to Sampson playing Chief Bromden in ‘One Flew Over the Cuckoo’s Nest’.

Who Framed Roger Rabbit? - Christopher Lloyd’s character is looking for Roger after smashing up the Trolley Depot bar and one of the drunks tells him “Yea I seen a rabbit. He’s right here. say Hello Harvey.” At which point if you’ve seen the 1950’s Jimmy Stewart comedy ‘Harvey’, about a man whose best friend is an invisible rabbit, feel free to bore anyone else who might be in earshot by explaining the joke.

On the original DVD for Bring it On, there’s an easter egg in the menu somewhere.

The Easter egg is a 5 second clip of the director saying “congratulations, you found the Easter egg.” That’s it.

A couple ones from The Matrix I found interesting:

We first meet Neo in room 101 (his apartment) and Trinity in room 303.

Toward the end of the film when Neo is running from agent Smith, he runs past a TV showing a scene from The Prisoner, a 1960s sci-fi show that was partly the inspiration for the movie.

Jack Black was in the movie ‘Waterworld’. It’s before he was a big name, so he isn’t given any special camera treatment as one of the raiders.

The alien queen in ‘Alien: Resurrection’ is the same prop as in ‘Aliens’. A fan had bought and stored the prop for years and loaned it back to the studio for filming.

The eyes of the Cryptkeeper puppet in the TV series Tales from the Crypt are the same two eyeballs that were used for Chucky, the doll from Child’s Play.

In the same vein of Back To The Future. When Marty goes back in the past he leaves from Twins Pines Mall. When he gets in the past he knocks down a pine tree and the farmer yells, you killed one of my pines.

When Marty gets back to the present it is now called Lone Pine Mall.

This man in Monty Python’s Life of Brian is none other than British comedy legend Spike Milligan, who, together with Peter Sellers and Harry Secombe, starred in the 1950s radio comedy show “The Goon Show”, which all members of the Pythons cited as their most important influence.

By coincidence Milligan was visiting his old World War II battlefields in Tunisia where the film was being made. The Pythons were alerted to this and he was included in the scene being filmed that morning.

In Die Hard where McClane jumps from one air vent shaft opening to another, he misses the opening he was aiming for but catches the ledge of one underneath it.

The take used was of a mishap where the stunt double fell further than intended, leading to the editor’s decision to have McClane catch a lower ledge mid-fall.

imo it makes the scene more intense and impressive (less realistic but hey, action movie logic)

the source (a Wikipedia citation, which is how I learned this bit of trivia)

In the 2009 Star Trek Kelvinverse film, there’s a scene where the Enterprise comes out of warp directly into a debris field. For a brief moment, R2D2 can be seen floating through that debris field.

Dr Hannibal Lecter said he ate liver, fava beans, and Chianti, because those are all foods you can’t eat when taking MAOI antidepressants, he was saying he wasn’t taking his meds.

During filming of the original “The Pink Panther” (1963) movie, actor Robert Wagner was blinded.

While shooting a bubble-bath gag scene involving an industrial-strength foaming agent, the chemicals burned the skin of both Wagner and his co-star Capucine. Wagner was reportedly temporarily blinded for several weeks after being submerged in the foam, with corneal irritation so severe that he could not see clearly for a period of time.

https://www.tcm.com/articles/960953/behind-the-camera-the-pink-panther

Really, there’s a tragic litany of incidents like this going all the way back to the Nickelodeon era. Production folks sometimes screw up, leading to actors and stuntpeople getting hurt, or even killed, as with Brandon Lee in “The Crow,” or with The Twilight Zone movie, in which three actors were beheaded / fatally injured by a helicopter crash.

https://en.wikipedia.org/wiki/Twilight_Zone_accident

I Dream of Jeannie / Barbara Eden was married to Klingon Kang /Michael Ansara.

Not really an Easter Egg, more just an interesting fact. In the movie Youth in Revolt there is a scene where the two main characters purchase a camper. The man they buy the camper from is played by Michael Collins, the third crewman of Apollo 11 who remained in orbit while Neil Armstrong and Buzz Aldrin landed on the moon.

The Batgirl film was scrapped by WB for taxes break purposes.