She leaned a seductive hip against the bar and flashed me what used to be known as a come-hither look. Dark-haired, sultry and shapely, the Latin temptress shimmied across the floor in a neon pink dress so clingy it looked sprayed on. Every inch of her impossibly long legs was on display.

Through pouty lips, she whispered her come-on in breathy Spanish. But it needed no translation:

"Espresso, big boy?"

I'd stumbled into a uniquely Chilean institution that's as quirky as it is popular, at least among men. Known as café con piernas -- "coffee with legs" -- they're a cross between a coffee bar and a Las Vegas cocktail lounge. No alcohol is served, just espressos, cappuccinos and lattes delivered by waitresses in distractingly revealing outfits.

This is no seedy, red-light-district phenomenon. Cafés con piernas are all over Santiago, on nearly every street corner in the modern, prosperous shopping district near the Plaza de Armas. There was one next door to our hotel, another a few steps around the corner and yet another across the street from that one. They're as ubiquitous in Santiago as Starbucks is in San Francisco.

They even have their own chains: the Café du Brasil, Café Caribe and Café Haiti franchises looked to be a tad less risque, while the Café Ikbar and Baron Rojo outlets were said to push the envelope in the other direction.

I'm not a coffee drinker, so I grabbed my saintly and highly caffeinated wife, Jeri, and insisted we go out for a little morning eye-opener. The Café Haiti near our hotel was a bright and airy place, with floor-to-ceiling plate-glass windows. There was absolutely no attempt to disguise what was going on inside.

It was 8:30 a.m., and the place was crowded with businessmen on their way to the office. There were a couple of female customers, too. They looked as if they'd been dragged in by male colleagues, and from their body language they didn't appear terribly comfortable. (According to an old Internet posting, there was a café con piernas for Santiago's feministas called Café Only Cyber Woman -- really, that's the name -- with half-naked waiters. But I could find no evidence that it's still in business.)

Jeri and I found an open spot at the stand-up bar. The waitresses wore dizzyingly high heels and walked on a platform behind the bar, so the hems of what passed for their skirts were right at eye level. The walls were covered in mirrors. Once you learned the caroms, you could check out your favorite waitress from any angle.

But here's the thing: No one did. There was no leering, at least that I could see. The men sipping their espressos barely looked up from their copies of La Nación to notice the micro-miniskirts passing by their noses. I saw no flirting. The scene was about as erotically charged as a Denny's. Maybe it was just too early in the day.

Nobody I talked to could agree on how cafés con piernas got started, but several Santiaguinos suggested it originally had something to do with Chile's curious affection for instant coffee. This much was true: On a continent that literally produces mountains of high-quality coffee beans, Chileans seem to prefer Nescafe. Order a cup of coffee in a restaurant or hotel, and likely as not you'll get a pot of hot water and a jar of brown powder.

In the mid-1960s, according to one version of the story, an entrepreneur decided that Chileans were ready for European-style espresso bars. He opened a couple of them, and they immediately flopped. In desperation, he outfitted his waitresses in Twiggy-style miniskirts, and male customers poured in the doors. Competitors rushed to copy the idea. An odd new Chilean institution was born.

Their popularity is surprising -- or maybe it isn't -- because Chile is probably the most straitlaced, socially conservative nation in Latin America. Divorce was illegal as recently as two years ago, and movies were heavily censored until 2002. More than 1,000 films were banned, including "The Last Temptation of Christ." You had to be 18 to view such racy fare as "Casablanca." Polling places are segregated by gender. Abortion is still illegal, and polls show a majority of Chileans want it that way. (Things look to be changing, though, with the recent election of Michelle Bachelet as Chile's first woman president.)

I didn't have the nerve -- or the command of Spanish -- to ask the Café Haiti customers why they were there. But a few years ago, Miguel Angel Morales, a café con piernas regular, told Salon.com: "Before, a man who wanted to see a beautiful girl had to shut himself up in a nightclub, and arrive home late. Here, he drinks his coffee, and five, 10 minutes later, he leaves and goes home or to work. There's nothing more to it than that."

I heard about two innovations that were ratcheting up the risque factor, neither of which was in evidence at Café Haiti: mirrors on the floor, and something called the "happy minute," during which waitresses drop their tops for 60 seconds. I'd also heard from more than one person that cafés con piernas were fronts for prostitution. This just didn't seem possible.

But then someone told me to check out the cafes tucked away in the shopping arcades. Downtown Santiago is full of Old World-style arcades lined with boutiques, watch shops and hair salons. I explored the one next to my hotel and found my way to Café Ikbar, which had mirrored windows and disco music thumping through the closed door. There were at least three cafes like this in the arcade. They were nothing like Café Haiti.

I pushed open the door -- the things I do for you readers! -- and when my eyes adjusted to the black-light darkness I saw waitresses in thong bikinis sitting on the laps of customers. The men had what looked like espresso drinks in front of them, but the ingestion of caffeinated beverages didn't seem to be the point of the place. It had the vibe of a low-rent strip club. I quickly backed out.

There are periodic attempts to shut down the cafés con piernas -- especially the ones like Café Ikbar -- and perhaps it will finally happen under Bachelet. It will be a long-sought victory for Chile's women and one more nail in the coffin of machismo. But as they're replaced inevitably by Starbucks, the world will become a little less quirky, and a little less interesting.