A group of U.S. movie studios, TV networks and professional sports leagues unleashed their fury and their lawyers on a small Canadian company yesterday, filing a pair of copyright-infringement suits that seek to shut the company down.

Toronto-based iCraveTV.com was sued for offering live television programming from 17 U.S. and Canadian stations for viewing on personal computers. Not to be confused with WebTV Networks--a service that essentially pipes Internet Web sites to televisions--iCraveTV brings conventional TV broadcasts to Web surfers who download video-streaming software.

That has infuriated a handful of companies--including 20th Century Fox, Walt Disney Co. and the National Football League--that contend iCraveTV is infringing on copyrighted material and violating U.S. law. If the company wants to broadcast TV programming online, it must negotiate a price for that content just like any other station, the companies say.

"It's brazen thievery," said Jack Valenti, chairman of the Motion Picture Association of America, a plaintiff in one of the cases. "We're going to ask a judge for a preliminary injunction, and if that doesn't work we're going to take them to court."

In a statement, iCraveTV chief executive William Craig said he had not had a chance to review the two complaints filed yesterday against the company but added that iCraveTV is acting in compliance with all applicable laws and will defend itself vigorously in court.

The skirmish is likely to be the first of many. With easily downloadable software, a computer can now play TV programs, though anyone with a standard modem will find the images are now far more herky-jerky than on a typical Sony. Still, advances in Internet technology, the proliferation of cable modems and quicker download times are turning Web television broadcasts into an appealing reality for a growing number of Internet surfers. Couch potatoes can become office potatoes; fans of "Days of Our Lives" can watch their daytime soap while working on a spreadsheet or sending e-mail.

The technology is an exasperating challenge to traditional content providers, such as TV stations and movie studios, which confront the possibility that thousands of Web "stations" will cash in without paying royalty fees. Preventing a proliferation of iCraveTV imitators, Valenti said, is a top priority.

"If we don't stop this right away, it's like a contagion that will spread," he said. "We'll go after any sites in the world that use our programs illegally, and we'll make it clear that this won't be easy stealing."

Calling itself the first company to offer live Web television, iCraveTV claims to have attracted about 800,000 visitors in December, after its launch on Nov. 30. Programming appears in a small screen-within-a-screen on the computer monitor, and the company collects fees from advertisers who pay for space that frames the TV window.

In the past, Craig has argued that Canadian law allows the company to broadcast TV signals online. He has also said that he would like to pay copyright holders for their programming, the same way that cable stations now do.

One of the suits filed yesterday teamed the NFL and the National Basketball Association, and another was brought by a coalition that includes Fox, Time Warner Entertainment, Columbia Pictures Industries and Paramount Pictures. Lawyers for the two groups of plaintiffs coordinated the timing of the litigation, filing them both in federal court in Pittsburgh.

An NFL spokesman said the league wants the company shut down immediately, and certainly before the playoff games this weekend. Damages of $150,000 per broadcast are sought by the leagues, in addition to unspecified penalties.

"ICraveTV is infringing," said NFL spokesman Brian McCarthy. "We must protect our rights and the integrity of our broadcasts."

CAPTION: William Craig, chief executive of iCraveTV, displays a laptop showing the Toronto-based company's TV broadcast site. The company is being sued.