Many writers are fanboys, just like us. That said, it is not unreasonable for them to want to throw in some reference to one of their favorite works. Sometimes, however, said element is a bit more blatant, and a lot more physical. This is the idea behind a Cameo Prop. It originally has nothing to do with the work of fiction or the series it is appearing in, but, usually, for sake of novelty, someone throws it in.
Let's say an episode of a show involves Bob going to an auction and winning the Ruby Slippers worn by Judy Garland when filming The Wizard of Oz. The rest of the episode might involve Bob wearing them (much to everyone's amusement), and even reenacting scenes from the movie. Almost always, he'll end up losing them in the end.
- Example A: A DMC DeLorean appearing in a Die Hard movie. This model of car is famous for being that of the car from Back to the Future, however this is an ordinary DeLorean. Not a Cameo Prop.
- Example B: The DeLorean from Back to the Future appearing in a Die Hard movie, complete with all the gear on the back, flux capacitor between seats, time gauge, everything. A Cameo Prop.
- The Star Trek/Legion of Super-Heroes crossover miniseries includes a scene where the villain informs the heroes that they are not the first time travelers to attempt to thwart his schemes. He shows them a huge room with at least 20 different impounded time travel devices, including a Stargate, a modified DeLorean, and even a Hot Tub Time Machine.
- In one Jon Sable, Freelance story, The Maltese Falcon (the actual prop used in the 1941 film) is a literal example, and the MacGuffin.
- The first Inspector Gadget movie, when the character receives his trademark outfit. In the cartoon, the outfit was a Shout-Out at best. In the movie, however, he directly identifies it as the Gadget Suit from Get Smart.
- Evil Dead 2 famously has the Freddy Krueger glove hanging from a wall.
- The Hitchhiker's Guide to the Galaxy: The film version has a scene where one of the background characters is wearing the Marvin costume from the television version. In addition, a box of Starbix breakfast cereal (seen only in the animated Guide entries in the television version) appears as a physical prop in the movie (albeit with an updated design).
- RoboCop's trademark Auto 9 pistol appears in Sin City, as it did during the same part in the comics.
- Looney Tunes: Back in Action features several famous movie and TV aliens in Area 52, including two Daleks and the infamous Ro-man.
- Gremlins. In a scene at a science fiction convention, Robby the Robot (from Forbidden Planet) and the time machine from the 1960 film version of The Time Machine appear. They both act the way they do in the films: Robby talks as he did in Forbidden Planet and the time machine can actually go through time.
- Robbie the Robot has appeared in a bunch of stuff. He's even got his own IMDB page.
- The pod from 2001: A Space Odyssey is visible in the junkyard scene in The Phantom Menace.
- The laboratory equipment from 1931's Frankenstein (1931), designed by Kenneth Strickfaden, was reused decades later in two ways:
- In Mel Brooks' Young Frankenstein, the props were used in the same way as in the 1931 film. Prior to that, it was seen in an episode of The Munsters and in several less memorable films, including Blackenstein and Dracula Vs Frankenstein.
- Strickfaden's equipment even made audio cameos — in The Empire Strikes Back and later Lucasfilm productions, after sound designer Ben Burtt met Strickfaden and made audio recordings of his equipment in use. One particularly notable example is Raiders of the Lost Ark, where it provides some of the sounds of Nazi equipment malfunctioning under the influence of The Ark of the Covenant.
- In Predator 2, one of the trophies aboard the Predator's ship is an Alien skull. That the two species inhabit the same universe would later become canon.
- Captain America's shield (or at least one of them) appears in Iron Man 2.
- Who Framed Roger Rabbit: Eddie has The Maltese Falcon in his office, and Jessica's car is the same one Evelyn drove in Chinatown.
- An episode of The Drew Carey Show focused on Drew winning the Batmobile from Batman Forever. At one point, Louis and Oswald are arrested for stealing the car, dressed as Adam West-style Batman and Burt Ward-style Robin.
- Nathan Fillion took the catalyzer from Firefly and put it on the Castle set.
- Another Firefly example; Zoe's gun is the Mare's Leg from Wanted: Dead or Alive.
- Babylon 5 had an unintentional example: They needed a space suit for the episode "Babylon Squared", and went to buy one from a prop company they dealt with. The only spacesuit available was the one from 2010: The Year We Make Contact.
- The Big Bang Theory:
- Duke Nukem Forever contains a lot of these, usually as part of Take That! jabs at other shooters. For instance, at one level you find Master Chief's Power Armor from Halo; in others, you discover Dead Space Space Marine helmets (there is an achievement for finding all of them).
- In the original Tomb Raider game, The Ark of the Covenant from Raiders of the Lost Ark can be seen in her mansion. This was of course removed from the remake, Tomb Raider: Anniversary.