Now XXX would be an interesting sight.* You'll have to wait for another three games for it (XXVII is 27 in Roman numerals, XXX is 30)
A work set in the future will often take elements of the present day and refer to them as a way to show that it is our future and not a fictional place. One form this can take is for there to be a reference to a contemporary Long Runner, and show that it is still going strong.
The chosen long runner is usually one that is well known for having several Numbered Sequels, which means all you need do is bump the number up by a few dozen.
Usually a throwaway gag, or incidental background detail for the eagle eyed.
But as nothing dates quite as fast as science fiction, the reference might pass a later audience by altogether.
This trope was popularised in The Eighties, and the two most common film franchises joked about in the earliest examples were Rocky and Jaws, the former because it had already produced an unusually large number of Numbered Sequels, and the latter because it was often regarded as a Cash Cow Franchise remaking the same film over and over again, so conceivably they could carry on doing it forever.
Distinct from Oddly Named Sequel, which is where the work itself has a title which plays with the Numbered Sequels trope. Compare Sequel Snark.
DC One Million is set in the 853rd Century, on the date that Action Comics #1000000 (their oldest property) would have been published before DC decided to begin "Volume 2" of that title as part of the New 52. Despite being the source of the title of the series this fact never comes up in the story line.
Back to the Future II had a holographic advertisement for Jaws 19, directed by Max Spielberg (Steven's son, who was four years old when BTTF 2 came out), with the tagline: "This time it's really, REALLY personal." All Marty has to say is, "The shark still looks fake."
As it was probably supposed to be the next Xbox after the Xbox 360, it ended up being an underestimate if anything: the movie is set in 2020 but the Xbox One is supposed to come out in Fall 2013. By 2020 it may well be at the end of its lifespan.
In Woody Allen'sSleeper, which takes place two centuries into the future, a McDonald's sign shows the number of hamburgers served as 1 followed by a hundred zeroes (a googol). In real life, the chain ended the count at 100 million in 1994, replacing it with "billions and billions served".
Harley Davidson and the Marlboro Man at one point shows a billboard in the background advertising Die Hardest V, which is a bit of an odd choice as the film came out in 1991 when there had been only two Die Hard films made so far, and it takes place in 1996 which is really overestimating the rate of churning out sequels. Good job at predicting it would turn into a long-running franchise, though!
Now that the franchise has been sold to Disney and trilogy #3 is in the works, with further installments hinted at, this may become a reality...or even an underestimate.
"Ridiculous" isn't quite the word here given the low number and the actual franchise's reach, but one story of the Starfleet Corps of Engineers mentions an old (mid-21st century) film: Rocky VIII: The Clone Factor!
A Dead Ringers sketch of a deleted scene from Terminator 2 involves several Arnold Schwarzeneggers appearing from the future to tell Arnold to stop doing Terminator sequels (and Kindergarten Cop). Before Sarah Conner kills Arnold to avoid these sequels they're up to Terminator 23, then another Arnold appears and reveals there are no more Terminator sequels, but there is now a Kindargarten Cop 14.
His song "Yoda", while not being specific, still plays off the 80s-era rumors that The Empire Strikes Back would be the first of eight sequels:
I know that I'll
be coming back someday
I'll be playin' this part
'Til I'm old and grey
The long-term contract
I had to sign
Said I'll be making these movies
'Til the end of time....
And then, nearly twenty years later, Disney bought the Star Wars franchise and started production on a new series of films, which indeed take place after the original trilogy and are likely to feature the original cast as supporting characters.
The Jonas Brothers do this to themselves in the song "Year 3000."
Don't have the book anymore to check the exact number, but an early Shadowrun supplement with mock advertisements in its margins included one for "Ramboid X__", an apparent continuation of the Rambo franchise in which he's long since become a Brain in a Jar controlling a war machine.
Deus Ex: Human Revolution, set in 2027, has a poster for a Final Fantasy XXVII, a nod to Eidos' then-recent acquisition by Square Enix. Though given when the game takes place, and the actual rate at which the games have come out (14 as of 2011, with a 15th in development), the number isn't really "ridiculous", and if it keeps up the pace it's held, Square Enix might very well be putting out a 27th game around that time.
The poster also crops up at the ultra-secret Omega Ranch, twice, in the sleeping rooms of soldiers. One can only hope the game is co-op.
A PDA message in Doom 3 says "The new Quake-43 game blows my mind."
Space Quest IV, with its Time Travel theme, labelled its various time periods using sequel numbers. The post-apocalyptic future into which Roger was initially thrown is identified as Space Quest XII; the galactic mall in the Space Quest X period also tosses a reference to King's Quest XXXXVIII: The Quest For More Disk Space (back in the days before CD-ROM drives), which clocks in at a whole 12 gigabytes! It's also stated to be by Roberta Williams III.
Decline Of Video Gaming did this with about everything. Though a real Devil May Cry 4 has come out since the first video was made, the same fortunately does not apply to Metal Gear Solid 7: Sons of Daughters of Mothers of Best Friends of Cousins of Dogs of Fathers of Liberty or a Final Fantasy title with an endless jumble of Roman numerals.
But that movie featured the casts of both the original Star Trek and Star Trek: The Next Generation, signaling that the franchise was moving in a radically different direction. The joke presumes that they were just going to continue releasing Star Trek sequels with the actors from the original 1966 series (it should be noted that they did revert to the original characters by the 11th movie).
And another Rocky joke in "Lemon of Troy" (though another Rocky movie would come true, but it would just be called Rocky Balboa, and even if it did have a number next to it, it would be the sixth movie, not the seventh):
Adrian: Rocky, please don't go to Mars and fight the Martian. Rocky: I gotta do what I gotta do. Adrian: But there's no oxygen on Mars. Rocky: Yeah? That means there's no oxygen for him either. That Martian wants a fight, he'll get a fight.
On Lilo & Stitch: The Series, Lilo ends up in the future in her own adult body and is excited that she is finally old enough to go see a movie by herself. Sure enough, the theater's playing Wasp Mummies IX: Return of Another Final Chapter Part 2.
"I guess we missed a few sequels."
Inverted in Futurama, when the PlanEx crew meet the Beastie Boys. The Boys' later albums are all separated by several years, but this takes it further.
Fry: I love you guys! Back in the 20th century, I had all five of your albums.
Ad-Rock: That was a thousand years ago. Now we got seven.