Twenty years ago, on Oct. 2, 1994, Fox aired the fourth episode of the sixth season of The Simpsons. Penned by legendary (and legendarily press averse) writer John Swartzwelder, “Itchy & Scratchy Land” lampoons the Disney World experience. At one point, Bart and Lisa stop in the park’s gift shop. Intrigued by a display of novelty license plates, the former searches in vain for one featuring his name:

Bart: Look at all this great stuff, Lis. Cool! Personalized plates! “Barclay,” “Barry,” “Bert,” “Bort?” Aw, come on. “Bort?”

Child: Mommy, mommy! Buy me a license plate.

Mother: No. Come along, Bort.

Man: Are you talking to me?

Mother: No, my son is also named Bort.

The throwaway gag returns later, when an employee manning Itchy & Scratchy Land’s underground control room says, “We need more ‘Bort’ license plates in the gift shop. I repeat, we are sold out of ‘Bort’ license plates.” The joke is so inconsequential that the DVD commentary panel—which includes Simpsons creator Matt Groening, showrunner David Mirkin, and director Wes Archer—doesn’t bother to mention it.

But 20 years later, the bit is a like a secret handshake. Just uttering the word “Bort” unlocks joy in even the show’s most discerning, Comic Book Guy–like fans. “I always liked the joke,” Bill Oakley, a former Simpsons writer and producer, told me in an email, “but I am surprised it took on this legendary status.”

Why, two decades later, are people still referencing “Bort”? At its peak, The Simpsons brilliantly satirized American culture. But the show’s most enduring trait may be its ability to take something utterly inane and render it endlessly quotable. The show’s smartest lines aren’t necessarily the most memorable. Rather, that designation better applies to the kind of weird joke that can only have been made by The Simpsons. In an email, Chris Turner, author of the book Planet Simpson, called such lines “unmistakably Simpsonian.”

If you believe this theory is bunk, visit the website of your state’s DMV and try to order a “Bort” vanity plate. Chances are some other Simpsons obsessive has beaten you to the punch line. And the lucky few who have managed to snag one recognize that they are envied members of one of America’s most exclusive and nerdiest clubs.

When John Orr moved from Indianapolis to Austin, he had to wait a year before a “Bort” Texas plate became available. But as soon as it was, the musician plunked down the cash. “That’s the kind of thing I spend my money on,” he told me with a laugh. Soon after he attached the new plate to his Ford, he began noticing people in nearby cars laughing and taking photos. “I think people could appreciate that somebody like me could actually take the time and pay the money to put something like that on my vehicle,” Orr said. And, he added, “not just on a bicycle.”

For Link Lowe, finding a pre-made novelty plate with his name on it has been a lifelong quest. “Of course I’m never going to,” he said. Instead of continuing his search, the Oklahoma City middle school teacher decided to order a “Bort” plate. When it arrived in the mail, he went straight to his old Volvo. “I live in the arts district, so I am surrounded by Simpsons fans,” Lowe said. “I’m putting it on and a crowd of people basically formed. They were just, like, drooling over it.”

Reaction to the plate has floored Lowe. Drivers honk at him every day, he said. He became so worried someone would steal the tag that he reinforced it with security screws. (For a while, rather than risk theft, he displayed it inside his car.) Lowe claims that a Simpsons-loving police officer recently flashed his lights and approached him in parking lot. “That is the greatest plate I’ve ever seen,” the cop said, and then let Lowe drive away. “Occasionally you’re gonna come across those hardcore fans,” Lowe said. “And it does awkwardly bring you together.”

Stuart Hocking knows this from experience. When his company transferred him to Montana for a stretch, he decided to splurge on a “Bort” license plate. He was living in one of the least densely populated states in America, yet strangers regularly pulled up next to his truck and asked about “Bort.” Some had no clue what it meant, but others definitely knew. As strange as it sounds, a four-letter word on a license plate induced moments of genuine bonding.

That’s the strange beauty of The Simpsons. The show’s minutiae still turns full-grown adults into geeky children. Which is precisely why Kipp Buckingham, a hotel bellman in Tucson, is disappointed nobody has asked him about his “Bort 1” Arizona plate. But there’s a good chance it’ll happen soon. After all, Buckingham said, “Everybody likes The Simpsons, right?”

