In the 1954 Sabrina, with Humphrey Bogart and Audrey Hepburn, the uber-wealthy Linus Larrabee has a phone in the back seat of the limo that drives him around. It looks like a regular phone of the day, with a cord and everything.
The joke in Get Smart wasn’t about radio phones, which had been around for decades, but about the recent craze for miniaturization that had grown with the space race. That’s what allowed the phone to be hidden in a shoe.
Speaking of Back to the Future, when he orders a “Pepsi Free” from the soda clerk, and is told, “If you want a Pepsi, you’ll have to pay for it.” Pepsi has a caffeine free drink now, but the Pepsi Free slogan (don’t know if it was ever a trademark) is a thing of the past.
Well, since you brought up The Simpsons, there were a couple of jokes in the mid-90s about the horrible playing of the Denver Broncos of the NFL- one episode in which Homer imagines himself as John Elway helping the Broncos lose the Super Bowl, and another in which Homer’s megolomaniacal boss gives him the Broncos as a gift (he wanted the Cowboys.) This was before Elway and the Broncos ended up winning two back-to-back Super Bowls.
While we’re on the subject of Hillary Clinton, the Warner Bros. cartoons of the mid-'90s had a lot of Clinton jokes. At least one Pinky and the Brain episode shows Bill as an inept fool who needs Hillary’s help to run the White House, and a song about the presidents on Animaniacs as originally written featured a lyric “The one in charge, it’s plain to see/It’s Clinton, first name Hillary!” (This lyric was not used in the show, but did appear on the Variety Pack album.)
Yes, I pointed that out. Meaning the impracticality of Max’s having to remove his shoe to make a call. If he had simply carried the phone in his pocket, or even had one built into his wristwatch, there would have been no humor in it. And as I said, today you can stick your cell phone in your sock if you choose, so that dates the joke.
Pretty sure bin Laden has been on that list for a long time - since the first WTC bombings in, IIRC, 1993.
ETA: Beg pardon - he made it to the list in 1998.
Even then, though, Reagan’s Presidential aspirations were well-known. He’d made a serious bid for the Republican nomination in 1968, losing to Nixon, and very nearly displaced incumbent Ford in 1976. I don’t know who wrote this particular MASH* episode, but working in Hollywood it’s not likely they were unaware their governor wanted to go to Washington.
As for non-jokes whose meaning changed over time, there’s always the dedication of Rambo III, to the gallant people of Afghanistan. Also, an episode of CSI titled “Unfriendly Skies” that aired on December 8, 2000, in which a mentally-ill jet passenger becomes violent and irrational, assaults other passengers and even tries to kick down the cockpit door. Upon investigating, the CSIs determine he was beaten to death by the other passengers. The episode ends with Grissom rather tongue-cluckingly condemning them. Post Sept. 11, I’d say if a passenger tries to break into the cockpit during a flight I’m on, I will gladly beat him to death and not regret it for an instant, with a hearty “fuck you” for anyone questioning my decision.
They’d have to make some changes to the Constitution before that could become a reality…
Remember that episode of Sliders where they visted an Earth where matriarchy (well patriachy in a skirt) was the norm? Hillary Clinton was President of USA. I always thought it odd that her name was still Clinton since women were supposed to be in charge, but the joke wouldn’ve worked with President Rodham. There was even a scene with a actress playing her giving a speech. Supposedly the producers tried to get Hillary to play herself, but she backed out at the last minute.
On a related note, the opening gag from this special promoting the NBC series line-up for the 1965-66 season is based on a situation that was odd then but annoyingly familiar now.
On a Shelley Long-era episode of “Cheers”, Diane vouches for relationship therapist (played by John Cleese) by saying he helped “Chuck and Di” with their problems. Given what happened to their marriage a few years later, somebody hearing that now would not likely think that’s a ringing endorsement.
Well, there’s the Simpsons episode in which Bart and Lisa watch Steve Irwin torn to pieces by a crocodile and lament missing the “feeding frenzy”. His death made that joke either funnier or more tasteless, depending on your viewpoint.
Similarly, there’ve been a ton of jokes at the Red Sox’ expense before 2004.
And the Simpsons Super Bowl episode even involved the Denver Broncos. No mention (that I can recall) of Homer actually owning the team earlier on.
And there have been almost as many since (especially if you live in New York) 
Not a joke, but it’s changed it’s meaning none the less: the first line of Neuromancer is ““The sky above the port was the color of television, tuned to a dead channel.” Of course, televisions don’t typically display snow anymore and the novel now opens with a brilliant oversaturated blue sky. It’s cool because it’s still somewhat oppressive.
So on a similar note, I’m listening to the Pet Shop Boys song “Dreaming of the Queen.” It’s themed on death and tragedy - the repeated line in the chorus is “and there were no more lovers left alive” - with the implication being that it’s about AIDS. However, it mentions Diana, so I’d guess most people who hear it now would interpret it as being about her death somehow, even though it was released while she was still alive. Indeed, when they played it in concert, they used footage of her funeral cortège.
There was also a really weird coincidence in another of their songs, “King’s Cross,” in which they refer to “by a station called King’s Cross/Dead and wounded on either side” – it was actually released a short time before the fire at King’s Cross tube station that killed dozens.
This made me curious, so I checked the online OED:
(Thank you, Seattle Public Library account.) So the term long predates Amos’ song. Common? Harder to tell – though a quick Google Groups search turns up 6 hits on the phrase “burn a cd” before 12/31/1993, so it wasn’t unheard of. None of those refer to literal flames, but a couple of them mean “record and release an album” rather than “make a copy of a CD at home.”
At the very least, it makes the Amos lyric ambiguous.
Al Franken wrote Why Not Me? about his fictional Presidential campaign. His Vice President was Joe Leiberman (Franken made a joke about his entire cabinet being Jewish men). A year after the book was published, Leiberman was picked as Gore’s Vice-Presidential candidate.
In Airplane II, two character have the following exchange:
‘We need to bring back McCloskey.’
‘You know ever since Reagan fired the air traffic controllers he’s been completely senile’
‘But what about McCloskey?’
‘He’s about the same as Reagan.’
The joke obviously played differently after Reagan was diagnosed with Alzheimer’s.
If you’ve seen Futurama, you know the mass transit system in New New York consists of a network of pneumatic tubes. In the first episode, March 1999, a man steps into a tube station, says “JFK jr. Airport” and is whisked away. When JFK jr. died in a plane crash a few months later, the episode altered the man’s destination to “Radio City Mutant Hall.”