Sports producers are calling the famous "1st & Ten" yellow line the most important development in sports broadcast technology since Instant Replay debuted on ABC's Wide World of Sports in 1967.

But for Sportvision, the technology company responsible for the ubiquitous yellow marker, the popularity of "1st & Ten" is really just the beginning.

This year the company is hearing cheers for three new products that are winning big with baseball, golf and NASCAR fans. They are:

— ESPN's "K-Zone", a feature for baseball which tracks the exact path of a pitcher's pitch as it either misses or pierces the strike zone (it won the 2002 Emmy for Outstanding Technical Achievement);

— "Virtual Caddy", which allows a golf commentator to draw a line (using the same "1st & Ten" technology) on the grass to better display a fairway's natural incline or decline;

— and "RACEf/x", which uses Global Positioning Satellite (GPS) technology to track the exact location of every competitor throughout a NASCAR race.

What makes those products successful, Sportvision President and CTO Stan Honey said, is that "they take something that is important to the event... and make it easy to see in a way that's unobtrusive." 

The key word here is "unobtrusive." That's the mantra the company adopted after Honey developed the controversial glowing hockey puck for Fox Sports while working as Executive VP of Technology for News Corp. in 1996.

News Corp. is the parent company of the Fox News Channel, which operates FOXNews.com. Fox is a minority investor in Sportvision, a private company.

"The puck system was not hugely successful," says Honey. "50% of the fans liked it and 50% didn't. It was controversial because of the glaring graphic we put on top. Since then we've built systems that are a lot more subtle in their implementation, like the first down line."

Despite the disappointment from hockey fans, Fox Sports president David Hill sees a continuous technological evolution in sports television

"Instant replay for me was THE technological innovation, followed by the telestrator," Hill told FOXNews.com. "Both those moved sports television light years ahead. Then comes the glowing puck, which was the granddaddy of them all. Then was the ability to electronically mark the "1st & Ten", and because football stands higher than other sports, this was the technology which made mass impact."

(Click here to see how "1st & Ten" works.)

RACEF/x, which allows viewers to track their favorite cars in a NASCAR race, is yet another step up in that evolution.

Every official Nascar car is now equipped with a Sportvision box, which contains two GPS receivers, a computer, sensors to measure rpm, throttle and brake position, and telemetry equipment which sends all of that information five times every second to the control room. All of that information is then displayed on-screen, and pretty soon on the Internet, where a Nascar fan will have the ability to follow the progress of their favorite driver even if that driver is bringing up the rear.

Sportvision charges networks about $25,000 per football game to use the 1st & Ten line. That price proved too steep for Fox Sports last season — so they cut it from the broadcast. The move caused such an uproar from fans that Fox brought the line back with the help of Intel, and all the controversy ultimately helped Sportvision become a bigger name in the broadcast world.

Now, it's Interactive TV that the company has its sights set on.

"We've really only begun to touch the surface of what we can do," Sportvision CEO Bill Squadron told FOXNews.com. "The real test will be in 2 or 3 years when interactive television becomes ubiquitious, when the fan will be able to customize their experience."

Honey shares the vision, but he's a bit more cautious. "We're still working on the success part, life is still a bit of a struggle. If we are to continue to succeed at it it's because we do things that are important to the viewer and therefore important to the broadcaster."