Comes now the minor miracle of the Week After Christmas, 2006. These are the days when liberal-arts majors finally crossed the line, falling into an emotional relationship with a robot. Not one on a movie screen, but one that scoots around their ankles, scaring the bejesus out of their cats — isn't that fun to watch? — while actually being quite useful.

This week, women all over America — and not a few men — are cooing and doting over their surprise hit Christmas present. They swoon when it hides under the couch and plays peekaboo. When it gets tired and finds its way back to its nest, sings a little song and then settles into a nap, its little power button pulsing like a beating heart, on, off, on, off, they swear they can hear it breathe.

It's as cute as E.T., as devoted as R2D2, more practical than a robotic dog and cheaper than some iPods.

It's a Roomba, an artificially intelligent floor-vacuuming 'bot, and this is the year mountains of them rumbled off the shelves not just of nerdistans like The Sharper Image and Brookstone, but of mainstream players like Costco, Sears and Target. They landed on the floors not just of innovators and early adopters, as in the previous four years, but of the hip majority targeted by "Saturday Night Live."

More than 2 million of the machines, which range in price from about $150 to $330, have been sold. The day after Christmas, a Roomba was among the top 20 items in Amazon.com's vast home-and-garden section, ahead of the top-selling iron, the top-selling blender, the top-selling coffeemaker and the top-selling George Foreman grill.

"The Roomba is wonderful!" says Kazuko Price, a family practice physician in Alexandria, Va., who says her patients include a lot of "kids who come in and mess up." Her robot cleans four rooms. "Well, sometimes he's dumb. He keeps going back to the same place. I kick him." She's named hers Robert.

Why does she think it's a boy? "Because I'm a she, that's why. I like guys."

On www.Epinions.com, a reviewer named Leisure Larry writes: "This was the first household item ever I gave my wife as a Christmas present. ... I don't think many husbands would even dare and fewer would survive giving a vacuum cleaner as a Christmas present. It worked ... she was thrilled!!"

She's named it Karlson.

These people are onto something. The wonder is only marginally about dust bunnies. It's about robot love.

The cultural moment when the walls between human and artificially intelligent machine began to tumble arguably came a couple of years ago when an "SNL" skit imagined a product called the Woomba, "the first fully automated completely robotic feminine hygiene product." That moment can now be revisited on YouTube.

This week, however, the cinematic moments occur in homes. Visit new Roomba owners and the scene is like those old war movies where you can hear the sounds of conflict, but all you can see are the faces of onlookers, cringing and turning away. The thumps and bumps under the bed finally end and suddenly these faces break into rapture as the Roomba emerges — covered with dust, but victorious.

You can just envision tomorrow's movie pitch. A vacuuming Roomba falls in love with a Scooba — the model that is designed to wash floors. They have a child. It is raised to know its place, as a lawn mower. But you know these kids. They have dreams. Real robots roam. It yearns to meander around Mars.

No less an authority than Bill Gates announces in the current issue of Scientific American that 2007 is the year the robotics industry will take off the way the personal computer industry did 30 years ago. "Some of the world's best minds are trying to solve the toughest problems of robotics," he writes. "And they are succeeding."

"We could have made the Roomba cuter," says Colin Angle, the chief executive officer of iRobot, the Massachusetts firm that makes the Roomba and Scooba as well as a host of military robots. "But we wanted to make sure this product was taken seriously. Rather than put a little bunny on top, we hit the efficacy message over and over again, because it appeals to the busy homemaker who has the job that needs to get done.

"And then she decides it's cute. The epiphany is when adults start talking about it as a helpful member of the family. You get them saying 'I do this and Rosie does that' or 'We can't imagine Rosie not helping us."'

Indeed, the vast majority of Roombas get named, according to Angle. Kids name 40 percent of them when they're barely out of the box. The naming decision leads to questions of whether a Roomba is male or female. Rosie is the most common name, says Angle, after the robotic maid of "The Jetsons."

But the Roomba does seem kind of male, in an eager-to-please fifth-grader way. Adding to its Y-chromosome cred is that you wish it had a little more memory, and that its meanderings weren't so random. There's even a group on Amazon discussing why so many people view Roombas as male, although one contributor says, "Our Roomba is named Rhonda" and accordingly now sports "ponytail stickers and googly eyes on it to give it more personality." You see, the robot used to freak out the owner's toddler daughter. But after they converted it into Rhonda "she fell in love with 'her.' "

So, a note to future historians: Not only are our helpful robots no longer the preserve mainly of gear-heads and toy-freaks. This is the year for a lot of mainstream Americans that our robots emotionally became one of us.