Back in the dying days of the monarchy, when the royals decided to bolt from France, they made sure to travel in the excess to which they were accustomed: in a bespoke carriage with the latest luxuries. The seats were padded, the walls were swathed in leather and taffeta (or so wrote Timothy Tackett in When the King Took Flight). And just in case they had to take care of some royal business, there was, yes, a leather-swathed chamber pot for their aristocratic bums.

No wonder the masses rose up.

But now, more than 200 years later, it seems that an American businessman has dared to share their dream. He too has bought himself a “carriage” of sorts—a rare 25-foot vanity-mobile called the Mauck MSV—and, like the monarchs of old, he has hired a group of cutting-edge customizers to make it snazzy: to install a shower, a refrigerator, and a dashboard modeled after the 1988 C4 Corvette. And just in case he has to “go” on the road, he has asked the customizers to make him his very own traveling throne: a commode covered, base to lid, in leather.

“It’s been totally hand-upholstered in leather by us. The whole thing is leather—and it’s waterproof leather,” said Matthew Figliola, the founder and owner of AI Design, the Westchester-based customizing company that was hired to create the hide-covered latrine.

It was a recent Friday afternoon, and Mr. Figliola, 39, was standing in AI Design’s vast Tuckahoe headquarters just 20 miles from New York City. Tall and loping, with affable eyes and fuzzy, Monchhichi hair, he was showing off his company’s creation with a mix of pride and irony. “You can see it’s really expertly done,” he said.

“But,” he added with a chuckle, “I was asked to do that. That wasn’t something I came up with. I mean, that’s pretty crazy—that’s pretty out there.”

Mr. Figliola is a master connoisseur of things crazy and out there. As head of AI Design, a kind of Willy Wonka fantasy shop for car-customizing fanatics, he has spent the last 15 years satisfying the automotive whims of the rich, ridiculous and auto-obsessed.

These whims go well beyond your standard supermega sound system and 24-inch car rims. They explode in bursts of speed from souped-up engines, glow through infrared night-vision systems and bling from the “mobile offices” that have become all the rage among the execs that frequent the shop. They manifest themselves in some of the craziest concoctions this side of reality TV—while making you wonder whether the four Ferrari-men of the Apocalypse are about to arrive.

“They’re the only guys to go to; they’re the Prada of the guys who do this,” said Alexander Roy, the speed-demon devotee of the annual playboys’ car rally, the Gumball 3000, whose cobalt BMW M5 has been turned into a latter-day Kitt by the AI Design wizards (think specially installed aircraft radios and a Raytheon thermal night-vision camera in the grille). “People will ship their cars [to them].”

The King of Morocco was once a customer, as was DC Shoes co-founder Ken Block and fallen Republican lobbyist Jack Abramoff (a nearly $50,000 client that the AI Design team would rather not discuss). In 2005, several papers reported that hip-hop magnate Sean (Diddy) Combs commissioned them to turn a dowdy cargo van into a monogrammed pleasure-mobile. It featured everything from a wine cellar to hardwood floors, and cost enough money—$350,000!—to help more than 40 homeless families get housing for a year. Ah, well!

“I think these days it’s about personalization,” said Michael Cajayon, a devoted AI Design customer (and Sirius Satellite Radio’s East Coast district sales manager), by way of explaining at least part of the shop’s appeal. “There’s guys out there with a lot of income that just want the car the way they want it. They want orange wheels …. They want a red interior …. They want bigger brakes …. They want it faster.

“It’s just endless,” he said. “It’s never enough.”

ON THE RECENT FRIDAY AFTERNOON, AI Design’s hangar-like headquarters was buzzing with the whir of business and the sound of Puccini. Strains of Turandot washed over the sound system (Mr. Figliola is a Puccini buff) while the shop’s 11 or so car shamans fiddled with the sports cars and trophy vehicles that had been rolled into the garage.

In the first spot, just behind the rolling garage door, hulked a blue-black Range Rover—the property of a long-legged member of the New York Knicks who needed his seats adjusted by a foot. Behind that, a patrician 1959 Mercedes that had been brought in by its “Wall Street type” owner for basic restoration and repairs. There was also a silver Porsche that had been rejiggered to look like an RSR race car, Mr. Roy’s blue Beemer (in for some post-racing touch-ups), and, looming above them all, two monstrous Mauck MSV’s—one gray, the other black.

“It’s a very big project. It’s probably the biggest project we’ve ever done,” Mr. Figliola said, pointing to the gray Mauck, which arrived in the shop in early November (and which also begat the other Mauck project, after the second one’s owner caught sight of it). “There’s hot water, there’s a bathroom, there’s a shower, there’s two sinks, there’s essentially living space inside”—and, of course, there’s a leather-coated toilet.

But such details are really just the humble beginning of the Mauck’s gussying-up. As laid out over three oversized pages of instructions, written by the Mauck’s owner and taped to the vehicle’s windows, the finished road-mansion will also have roof-mounted photovoltaics, a Hummer night-vision unit, a “Pullman-type bed,” a “cab-located” computer “office” (complete with flip-down keyboard and 17-inch screen) and at least 20 other absurd Batman-style gadgets.

“This client is very involved. He doesn’t do golf, he doesn’t do the country-club thing—he likes doing this,” Mr. Figliola said. “He usually spends like three hours here on Saturdays.”

Mr. Figliola, who is as sweet as a teddy bear but protects his clients like a grizzly, declined to get specific about how much this customer is shelling out for his hobby, offering only the vague confirmation that “it’s definitely six figures.” Nor would he give up his client’s name or profession, except to say that he is in “business” and has purchased the vehicle as a sort of high-end family truckster to tote his wife and kids to the “equestrian events” they apparently frequent. The idea, Mr. Figliola explained, is that the Mauck will function as a kind of “mission control” at these events, a command center and retreat that will be decked out with enough finery to make it plush and enough gadgetry to make it Bond-worthy.

“He’s more coming from the aspect of ruggedness, post-apocalyptic survival,” Mr. Figliola said. “He wants to be able to be in any situation and handle it.”

All of which naturally begs the question of whether this 21st-century New York businessman encounters such life-threatening situations on a regular basis.

“No, I think he just likes it,” Mr. Figliola said, with a sly smile. And then he added: “This is definitely a vanity-based business. I mean, there’s a small part that’s necessary, but for the most part, it’s a hobby. It’s boy toys.”

WHEN MR. FIGIOLA FOUNDED AI DESIGN BACK IN 1992, he was just a 25-year-old kid with chubby cheeks, slicked-back hair and an earnest grin beneath his brown goatee. He had been working on cars since he was 16—a passion for music and audio systems had gotten him into the biz—and, after nearly a decade fixing up cars in other shops, he had decided it was time to break out with his own custom-tastic car outfit.

“It was tiny,” said Mr. Figliola of his company’s first home. “It was me and two other individuals, who were actually twins. And I think it was like a 2,000-square-foot, dungeon-ous shop in South Yonkers.”

But then the mid-1990’s arrived and, with them, the dual power-fads of the start-up boom and the S.U.V. revolution. Much like today’s hedge-fund frenzy, the start-up boom flooded the leisure caste with money, ego and technology, while the S.U.V.’s provided the canvas onto which to project all that excess. (People apparently are keener to modify trucks than cars, Mr. Figliola explained). And since AI Design was already riffing off the whole S.U.V. thing, dabbling at the cutting edge by implanting TV’s in headrests (Mr. Figliola maintains that he was the first to do it, in 1992), the people began to flock.

“It took us from doing small work to large work almost inside of a couple of years,” he said.

That work was wild, unrivaled and lucrative enough to make Mr. Figliola a decent living (though he said it’s still “an algebra test every day”). But it hasn’t always been easy. Or at least the gents (and, occasionally, ladies) who order up the jobs haven’t always been easy. While Mr. Figliola was careful not to harsh on his clients—and while he confessed to fond feelings for many—he couldn’t hide the wry smile that slipped across his lips when asked what it was like, say, working for Mr. Diddy.

“Interesting,” he said with a knowing giggle. “It went O.K. It was just tough because he put so many people in front of him. He didn’t want to deal directly with me.”

As for King Mohammed VI of Morocco—at the time, simply Prince Mohammed—dealing with his handlers was what one might call a royal ... privilege.

Back in 1997, Mr. Figliola was hired to spiff up the prince’s Lexus S.U.V. with a humidor, a computer, an audio system and “lots of electronic gadgets.” As requested, he did the work, shipped the auto east and then, one quiet Sunday morning, got a frantic call from his contact, Chichi, complaining that the car wouldn’t start. She ranted, she railed, she begged him to get on an airplane that day—which he did, jetting more than 3,600 miles. But when he arrived at the palace, he discovered that “there’s nothing wrong with the car”: someone had simply forgotten to put the battery terminal on after the Lexus had been transported.

Mr. Figliola is the kind of guy who can laugh at such adventures—in part, perhaps, because he’s too busy hatching ideas to be bothered. His latest is the Mobile Living Space, which he describes as “a line of vehicles” that will be “opulently outfitted with all the comforts of home.” They will have laser-engraved hardwood floors, 32-inch L.C.D. video monitors, aircraft lighting—the kind of stuff that would make a headless queen drool in her grave.

Strangely, however, for a man who spends his days dreaming up such concoctions, Mr. Figliola doesn’t actually long for one himself—or not really.

“I like the craft a lot more than I like cars,” he said.

One of the lesser-known perks for members of Congress is that the taxpayers will lease them a car (or two) for the purpose, of course, of official business.

Knight-Ridder has a handy tally of those leases, from most expensive to cheapest, and two New Yorkers finish near the top. Greg Meeks' Lexus costs the public $1,062.85 a month, putting him in seventh place nationally. Charlie Rangel, whose Cadillac DeVille costs $998.48 a month, is next.

At the bottom of the scale, Anthony Weiner's Chevy Impala, leased for $219 a month, is the third-cheapest car in Congress.

There's something about watching one of these mechanical marvels, barreling along the curb sucking up garbage, that fills me with a sense of well-being. It's the modest triumph of order over chaos, an especially welcome sensation in today's cockeyed world.

On the other hand, when a car is illegally parked, mocking the city's alternate-side-of-the-street parking regulations, and the vehicle (or "broom," as it's known in the business) is forced to swerve around it, leaving trash behind, my morning and my mood grow glum. I feel personally sullied.

My ambition of seeing the world from the cockpit of an official New York City street-sweeper came true early one recent morning (after two years of on-and-off negotiations with the Sanitation Department's P.R. office, I might add), when I was told to report to the Sanitation garage at 73rd Street and the East River.

I'd requested the route that passes by my apartment house. Call me self-centered, but as much as I want all of New York to sparkle, I don't have as much invested in, say, Washington Heights or the Rockaways as I do in my very own block. As fortune would have it, the Department of Sanitation was able to accommodate my wish. So early that morning, I clambered into the jump seat of a broom driven by Diego Martinez, a 13-year veteran of the department, and by 7:30 a.m. we were traveling "coast to coast," as they say in the trade-picking up garbage from the swank shores of Fifth Avenue all the way to East End Avenue. (Perhaps my proudest moment came when I saluted my wife, out walking our dog, as we soldiered past our building.)

The cab is very clean, and the ride isn't bad-no Lexus, admittedly, but not a Sherman tank, either. Then again, we were riding in a newer vehicle. "You don't feel the bumps as much as on the old ones," Mr. Martinez explained. "You're not hitting the ceiling."

It may be an exaggeration to say that you feel like the king of the city from the cockpit of your broom. But you certainly feel like a contributing member of society. Fifty-year-old Mr. Martinez waves to his buddies in garbage trucks, to fellow broom operators whose routes intersect his, and to doormen, porters and street vendors he's come to know during his six years driving the same streets. On this morning, even though the weather was overcast, the 180-degree vista through the cab's large, clean windows of New Yorkers industriously heading for work was almost enough to put a lump in your throat. The girl-watching wasn't bad, either.

My cabmate wasn't very forthcoming when I broached the subject with him, however. "No comment," said Mr. Martinez, who's a family man. His wife is a travel agent, and his daughter will be starting medical school this month. "It wouldn't hurt for her to take the test," Mr. Martinez said of his daughter, referring to the Sanitation Department entrance exam. He himself took the exam when his business-school plans didn't work out. "You don't know what the future holds," he noted.

Sanitation may not be the most glamorous city agency, but Mr. Martinez doesn't let that stereotype interfere with his self-esteem. "I tell people I'm putting my kid through school, and I'm doing it honestly," he said.

He explained that the solitude of working alone isn't for everyone. But you don't feel alone: If anything, you feel like you're in the Today show studio, the cameras on you. "People stop to watch the brooms-especially tourists," Mr. Martinez said. "They don't have it in their country."

There's also more than enough to keep the average person occupied: turning the water valves inside the cab on and off (depending on which side of the street you're spritzing), raising and lowering the broom to adjust for road conditions and obstacles, and-most important of all-using your mirrors to make sure that no garbage gets left behind.

The mechanically minded might be interested to know that the street-sweeper actually has three separate brooms: two gutter brooms, one on either side of the machine, and a pick-up broom in the center to which they direct the garbage. The pick-up broom pushes the trash-everything from Snapple bottles to squashed pigeons ("You can't leave them behind," Mr. Martinez explained stoically)-onto "flights," a conveyor that lifts the garbage into the hopper.

The job approaches art when Mr. Martinez must decide how much pressure to apply to his brooms by flicking a switch on his dashboard. He explains: "How heavy do your want your brooms to press against the street? The newer they are, the less pressure. As the brushes get worn, you start putting more pressure on them. I'm on 'light' now. They're fairly new."

Another mark of the true street-sweeping pro is being able to hug the curb as you turn a corner. "It's called 'sniping' the corner," Mr. Martinez explained. "If you go into a pothole or hit the gutter, the broom has a tendency to jump a bit and not pick up as well," the operator continued as we drove up Third Avenue. "That's why it's important for you to be looking at your mirrors all the time."

Indeed, so attuned is the sanitation worker to his machine that he tries to fill up at the same hydrant each morning-the one at the southeast corner of 68th Street and Park Avenue. "I know the water is going to come out clean," he explained. "You don't want the rust to clog up your spraying bar.

"You take care of the broom, the broom takes care of you" he concluded.

I took the opportunity presented by the lull in the action to purchase coffee and a roll from a breakfast cart across the street from Mr. Martinez's favorite hydrant.

"The other day, he showed me pictures of his family," Mr. Martinez said of the coffee-cart guy as he purchased a cup himself.

As much as he enjoys the quiet satisfaction of seeing a shining road in his rear-view mirrors, Mr. Martinez confessed that he lives for parades: the Thanksgiving Day Parade, the St. Patrick's Day Parade and, especially, the National Puerto Rican Day Parade.

There's nothing quite like the thrill of tooling up Fifth Avenue before an appreciative crowd, 10 deep, the wind throwing copies of Hoy or El Diario into your path, and a mechanical broom on each wing.

"They're dirty, but it's enjoyable to work," he confessed. "The Puerto Rican parade-forget it! Five or 10 brooms in formation. You feel like a celebrity."

I can see how he would-and not just on holidays. I'm pleased to report that my ride exceeded expectations, if such a thing were possible-if only because Mr. Martinez seemed to share my mania for nabbing garbage and putting it in its proper place.

"By the way, what are you supposed to do with your cup when you're finished your coffee?" I wondered. "It's very convenient," Mr. Martinez responded. "I throw it in front of the broom."

And so we did.