After receiving their briefings, operatives of the IO Corporation and The Coastline of England, a pair of fictitious shadowy high-tech firms organized into ten separate teams, fanned out across the city of Seattle, tracking their elusive quarry.

V-Quest 2000 is this year's installment of what has come to be known simply as "The Game," a high-tech scavenger hunt and race that has been run in different cities, including San Francisco, New York, and Los Angeles off and on since the mid-1980s.

"It's the most intense way to have fun that I know of," said Team Purple's Bruce Oberg, one of the founders of Sucker Punch Productions, a small Bellevue, Washington entertainment software company.

Over the next 24 hours, the agents visited an inmate at the county jail, led a cheer at a Seattle Mariners' home game, crashed a Samoan house party in one of the tougher sections of town, and scaled the top of Seattle's Space Needle as part of their mission.

Along the way, they also had to decipher codes embedded in a carton of eggs and on the license plates in a row of parked cars, and read the hidden message written on the tape of an audio book.

"For some of us computer geeks, it's the closest thing we'll ever get to a combat-level simulation, where you're just trying really hard to do the right thing for your team and win," said Oberg, who first became involved with The Game in 1995 while working at Microsoft, and has been participating as a member of the Purple Team ever since.

After taking first place their first year, he said they sat out the next, organizing the puzzles and performing the essential role of coordinators, coming back to win again in 1997. Oberg said that while The Game does involve its share of physical challenges, "it's nowhere near like a triathlon."

"I would say that it's more brain than brawn," he said, "but sometimes it's like, 'How do you get on top of that rock wall?' Sometimes you have to climb it." He said the activities mostly involve solving puzzles and finding clues, although part of the fun is that there are no hard and fast rules about any aspect of The Game.

"Before the game it's very interesting in figuring out what might happen, because anything might, to try to make sure you're prepared for any eventualities." Even finding the starting point involved hunting through HTML code on a number of fake Web sites during the preceding weeks.

Most histories of The Game have it starting with the first Bay Area Race Fantastique at Stanford University in 1986. But Joe Belfiore, who was there at the start and now works for Microsoft, said the real beginnings were with a group of high school students in Clearwater, Fla., a couple of years before that.

"My junior year of high school, my friends and I started getting bored between marching band season and springtime," Belfiore said. "We started putting on these races." The first game in high school was called Midnight Madness. He said they got their inspiration from a Michael J. Fox film of the same name.

"We saw the movie, thought it was a cool idea, and decided to make our own."

After graduating from Stanford, a number of them took jobs with Microsoft, and The Game was resumed along the banks of Puget Sound in 1994.

This year, veteran gamer John Tippett added an unexpected twist to what had always been a fairly low-key (if high energy) event by adding a $25,000 entry fee to benefit the World Vision organization's Vision Youth programs. This way, he was able to add some elements (like having the teams climb to the pinnacle of the Space Needle and flying Alaska Airlines' Flight Simulator) that would have otherwise remained out of reach.

To raise the entrance fee, some of the teams signed on corporate sponsors, including Amazon.com, Real Networks (whose employees made up the Blue Team), Verisign, and Microsoft.

Sunday morning, 24 sleepless hours after they began, the race ended in a literal sprint to the finish line, with three members of Belfiore's Team Silver racing through the gates at Pier 48, barely 10 seconds ahead of the first members of the Purple Team.

For their efforts they won some great stories, the bragging rights for another year, and the chance to set the stage for next summer's Game. That is, unless someone else decides to change the rules, since as Belfiore observed, "like the rest of the game, you can't count on anything as an established rule."