To anyone who has felt trapped in a circle of bad service: If you haven't heard the story of Mona Shaw, pull up a chair.

The 75-year-old Virginian had ordered a much-advertised package of services from Comcast, her cable company. The installers failed to show up at their appointed time. They came by two days later but didn't finish the job. Comcast subsequently cut off all her service.

Shaw and her husband decided to visit the Comcast office and speak to the manager. They arrived with their equipment and were directed to a bench. They sat there for two hours. Then a customer representative informed them that the manager had left for the day.

At that point, Shaw lost it. She went home and returned with a hammer. Yelling, "Have I got your attention now?" she bashed the rep's keyboard, attacked the monitor and destroyed a telephone. She was hauled off in cuffs.

But Shaw became a hero to every consumer who has wasted an hour talking to a telephone robot whose multiple-choice options never addressed the problem. Or who has clicked the e-mail address at "contact us," unloaded his or her heart and didn't receive a response.

The good news is that consumers no longer have to vent in a physically confrontational way. The computer keyboard has become a mighty sword — and invective, satire and parody provide the muscle. Thanks to the Internet, angry customers can get even while enjoying the community of fellow sufferers. BusinessWeek calls these tech-adept complainers, "consumer vigilantes."

It was Comcast's bad luck to antagonize Bob Garfield, a columnist for Advertising Age magazine. After failing to get service from the cable company, Garfield embarked on what he called a "consumer jihad." He launched an amusing Website, ComcastMustDie.com, where similarly frustrated consumers gather to share war stories.

The site features links to a podcast starring Mona "The Hammer Lady" Shaw — and a hilarious video spoof of a traumatized customer.

Wouldn't you know it? Comcast started contacting the customers who railed against it on the Website and offered to fix their problems. Soon people wanting service just posted their needs on ComcastMustDie.

A possibly naive question: Aren't unhappy customers bad for business?

It would seem so. Three years after Sprint and Nextel merged, the company's stock had plummeted 66 percent. "Poor service is the central reason," BusinessWeek reported.

Before the merger, Nextel had the lowest "churn" — customers who leave — in the industry. After the merger, no one seemed to care. (Sprint Nextel has reportedly gotten the message and is now on a campaign to spruce up its customer care.)

Back to the question, some businesses may have simply decided to live with a certain level of consumer dissatisfaction. They figure that losing a few customers will do less harm to the bottom line than the cost of hiring humans to help them.

But as ComcastMustDie and other sites, such as The Consumerist (consumerist.com), show, angry and skilled malcontents can cost a company more than a few customers. And there's the danger that some may be radicalized to the point where they stop caring about getting their repairs or refunds — and can no longer be bought off with a few hundred in coupons.

They're out for revenge. And if they're having a good time doing it, the prospects of their calling off the consumer jihad are greatly reduced.

The communications revolution is a two-way street. It enables companies to put considerable distance between their customers and a human service rep who speaks decent English — but it also empowers consumers to fight back. The result is a standoff that, it appears, consumers may win.

To find out more about Froma Harrop, and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate web page at www.creators.com.

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