After years of battling computer games for the attention of kids, Lego is fighting back with hackers, the Web and a robot on its side.

The Danish company has updated its Mindstorms line of buildable, programmable robots — a product that debuted to much fanfare in 1998 but that the company had let languish to near-extinction. The new Mindstorm NXT set is priced at $249, which positions it against perhaps Lego's biggest foes: video game systems, such as Microsoft's Xbox or Sony's PlayStation 2.

It has been tough for a company whose products demand patience and attention to detail to vie with not only Xbox but also the Game Boys, MySpaces and YouTubes of the world. In its worst financial year, 2003, Lego Group lost $238 million.

In deciding to revamp the aging Mindstorms robot line, Lego turned to its most faithful core of fans: enthusiasts and hackers who had banded together to form their own online support network. In 2004, Lego e-mailed four of its biggest Mindstorms fans across the United States. The team members spent 10 months advising Lego as the Mindstorms Users Panel, discussing their dream lists of what the next kit should and should not be.

Lego's star chamber, later expanded to 14 members, helped shape what the new robots will be able to do and which parts come in the 571-piece kit. One member was even able to pressure the company into building a part that makes its debut in the new Mindstorms set — a rare event at Lego, which treats every individual piece with reverence.

The resulting toy has much more up-to-date technology than the original set, including a USB 2.0 port for fast downloads and Bluetooth for wireless connections. With the right parts and programming, a Mindstorms robot can dance in response to sounds or follow the beam of a flashlight. Lego even decided to embrace the hacker community, which has spent years altering the electronic brain of the system to make the robots perform beyond what Lego had intended. The company is making public the new source code, which is the programming that runs the unit, and allowing users to modify it and share their changes, as long as they promise not to profit from it.

Toy industry analyst Chris Byrne got an early set of the new Mindstorms product and gave it a rave review in a phone interview, bragging that he was able to build a robot that he could control with his Bluetooth-enabled Razr phone.

While he said it will probably be a success in terms of toy industry standards, it's no Xbox killer. Mindstorms "requires patience and sophistication that people who like to blow stuff up in Halo might not have," he said, referring to the popular Xbox game.

While Lego listened intently to what its hard-core robot-building fans wanted most in the next Mindstorms, it did take concerns such as Byrne's into consideration. During a recent visit to Washington to show off the new Mindstorms, brand relations director Michael McNally said the original robot set took an estimated two hours to make. The new kit aims to cut that time to 30 minutes.

"Today's kids don't have two hours to do anything," he said.

Some ardent fans of the original Mindstorms kit bought the set for their children but ended up monopolizing the toy. Other parent-child teams report that they divvy up the tasks when building a robot: One builds the robot, the other does the programming.

That's how it works for David Schilling, an original member of the Mindstorms User Panel, and his son. Schilling, a former Microsoft programmer in Redmond, Wash., asked his wife for permission to buy the original Mindstorms kit, saying the kit would eventually be an entertaining and educational tool for their son, then 1. The original Mindstorms kit was recommended for ages 12 and older; the new one is for 10 and older.

Now Schilling has about 20 kits. And, yes, his son, 8, has become a Mindstorms fan. He helped build an automatic paper towel dispenser with Dad's prototype unit of the new Mindstorms set.