
Movie making has got to be an absolute blast. There's no other explanation for how pretty much every movie you've ever seen has some kind of weird joke hidden inside it just as an Easter egg for fans, obsessive compulsives, or in some cases, even the film-makers themselves. Below are all examples of actors, stunt-people, writers, and directors all making references to their previous work.
http://www.ranker.com/list/16-movie-in-jokes-you-probably-didn-and-_39_t-notice/jf-sargent,
Sean Connery in The Rock and... you know...
One of the most obvious ones we’ll encounter here, when Sean Connery says that he was trained by British Intelligence we all know exactly what he’s talking about.
If you haven’t seen The Rock, you can watch the whole thing on Youtube (until it gets taken down) or, if you just want the short version, you can watch this scene. You don't really miss anything.
Jeremy Irons in Lion King/Reversal of Fortune
No one plays “Creepy old guy” like Jeremy Irons. In The Lion King, when Simba says “you’re so weird,” Scar’s haunting response (“You have no idea”) would have been strange and foreboding even if it hadn’t been a repeat of the same line from an older film, Reversal of Fortune, where Irons played an arrogant and aloof British socialite accused of murdering his wife.
Which is actually not all that different from the plot of The Lion King... if you’re crazy. Or if you’re the person who made this (and are also crazy).
David Duchovny in Evolution/The X-Files
Does anyone remember Evolution? It was that movie that came out in the early 2000s that all the sci-fi nerds really wanted to like because it had David Duchovny in it and was about wacky alien monsters, but it actually wasn’t any good because it also had Seann William Scott and the jokes were all terrible? No? Well, there’s a bit (which you can see in the trailer) where David Duchovny makes a joke about knowing “those people” who work in the government, which most people took as an X-Files joke.
Michael Biehn Keeps Getting Bitten on the Arm in James Cameron Movies
James Cameron really hates Michael Beihn’s arm. First in Terminator:
Lindsay Brigman (Mary Elizabeth Mastrantonio) bites him on the hand. Proving that... uh...
...moving on!
The Nicholas Cage Beige Volvo Trilogy
Here’s a neat one that I found on TVTropes: Apparently Nicholas Cage really likes beige cars. He says he drives one in The Rock. Later, he drops Dave Chapelle’s body into one in Con-Air.
Proving that.... Nicholas Cage loves beige Volvos? If James Cameron ever directs a movie where Nicholas Cage bites Michael Biehn's hand while driving a beige Volvo then... then we'll really have something here.
Sylvester Stallone in Rambo/Tango & Cash
“Just who do you think you are?” “He thinks he’s Rambo!” “Rambo... is a p*ssy.”
(Sylvester Stallone played John Rambo in First Blood and all it's sequels. Obviously).
John Cho: Better Luck Tomorrow/Harold and Kumar Go to White Castle
Near the beginning of the film when Harold (Cho) tries to park his car, someone else swerves into the spot just in front of him and shouts “better luck tomorrow!” –the title of a movie Cho starred in just two years earlier.
Also, hidden in that film is another one: Justin Lin, the direct of Better Luck Tomorrow, would go on to direct Fast and the Furious: Tokyo Drift, Fast & Furious and Fast Five, which reuse the character of Han Seoul-Oh (Sung Kan). Does this mean that Harold & Kumar takes place in the same universe as The Fast and The Furious? I’m gonna go with “yes,” but I’ll let you guys in the comments figure out what that means, exactly.
Steve Carell in The 40 Year Old Virgin/Evan Almighty
The 40 Year Old Virgin wasn’t that good, so you have to be in a really s**tty movie to want to go back to it. Luckily, Evan Almighty was a really s**tty movie.
Jeff Bridges in Iron Man/The Big Lebowski
In the first Iron Man movie, as Pepper Potts (Gwyneth Paltrow) is trying to steal some information from Obadiah Stane’s (Jeff Bridges) mainframe, there’s a brief reference to an earlier film starring Bridges - it’s only one frame long, but it clearly says “Lebowski” and lists the origin port as “Long Beach,” making it a clear reference to Bridges’s much-loved role as Southern California burnout Jeffrey Lebowski in the Coen Brothers’ The Big Lebowski.

It’s an especially funny comparison since Obadiah Stane and Jeff Lebowski are pretty much polar opposites. The former is a multi-billionaire evil industrialist, the latter is... is uh... is this a... what day is this?
Ray Park in X-Men/Star Wars Episode I: The Phantom Menace
This one’s pretty cool, but unfortunately, you’re going to need the DVD or Blu-Ray (or I guess, like, the VHS?) to see it in full effect: Ray Park is the Scottish actor/stuntman/martial artist responsible for the only good thing about Star Wars Episode I.
He also played Toad in the first X-Men movie. You know, the guy with the tongue that got zapped out of the sky after Storm said that line about toads and lightening? Well, after he throws Storm down the elevator shaft, he grabs a long metal bar and spins it in exactly the same way you see him spin his lightsaber in Star Wars. It’s pretty neat, but again, it’s not online, though, so you'll just have to believe me.