(CNN) -- Sean Forman still remembers the final play of the final game on the final Sunday of the NFL season four years ago. And it still hurts.
Many fantasy football players this year will be counting on Indianapolis Colts quarterback Peyton Manning to put up the numbers he's become known for throughout his career.
It didn't matter that Arizona, which scored on a 28-yard touchdown pass, knocked Minnesota out of a playoff spot. He doesn't like either team.
Instead Forman, passionate about his Pittsburgh Steelers, was about to win his first fantasy football crown. He lost on that touchdown. Elation, bragging rights, the hundreds of dollars in the pot, they all disappeared on one improbable play.
Forman has four fantasy football drafts this week and continues to look for the winning formula. He is one of millions of fantasy players in the United States who daily check the Internet, read scouting magazines and watch ESPN trying to get an edge on their fellow competitors.
"I certainly want to do better than them," Forman, a 32-year-old analyst for a nonprofit education association, said of his league mates. With the NFL season set to begin on September 6, Forman and his competitors are devouring all the roster news from the 32 team camps.
Forman, who now lives in Reston, Virginia, estimated that he spends $300-400 a year and "way too much time" on fantasy sports. And that's not unusual.
More than 16 million Americans played fantasy sports in 2006, according to research by Fantasy Sports Trade Association, an industry group. Fantasy players are almost all male, the average age is around 36 years old and most make more than $59,000 a year.
Jeff Thomas, who runs a fantasy operation called sportsbuff.com and is president of the FTSA, says the average player spends nearly $500 when you consider league fees, magazines devoted to fantasy sports and pay content on the Web.
Thomas said that the revenue from the contest portion of fantasy is about $200 million but that when you figure in the ancillary money, fantasy sports is a $2-billion-a-year machine.
The impact on the U.S. economy is 50 to 100 percent more, he said.
"Our research shows that people spend more money on tickets, buy more sports merchandise and travel to more games," he said of fantasy sports players.
Playing in a fantasy league makes many people "better fans," said Matthew Berry, the top fantasy expert at ESPN.com. He also noted that fantasy players are "our most hard-core users."
Mark Bleckman, a 31-year-old financial analyst, agrees that fantasy players become more interested in the sport they are playing. A long-time member of a baseball league, he joined a football league last year.
He was a football fan, but admitted that he didn't know all the players in the league.
"I was a fan of my team," he said of his hometown Steelers, but added that after joining a football league, he was "more drawn to football than I was before."
But Bleckman said he plays fantasy sports mostly for the camaraderie. He has been playing in a baseball league for 16 years, since his sophomore year in high school. Some of his friends from those days are still in the league.
Only one still lives in Pittsburgh, Pennsylvania. Bleckman lives in Ann Arbor, Michigan.
Bleckman, who spends about $100 a year on fantasy sports, is the commissioner of the league, which means a weekly commitment to keeping league members informed of trades and other transactions as well as rulings made. He likens it to being a social chair.
"It's a great excuse to keep in touch with friends," he said. "We keep in touch through a chat page on CBS Sportsline," which provides the software and content to run the league.
Berry, said that ability of the Internet to link players in different states and different countries was one of the primary reasons the number of fantasy players exploded in the late 1990s.
"You no longer had to know 11 guys within driving distance," he said.
Some players who spoke to CNN.com said they have traveled for a league draft, but said that often the players who couldn't make it would send picks by online messenger or call on their cell phones.
Keeping stats and getting updates on league standings is much easier than the days when a commissioner would have to send out an e-mail on Mondays, with hand-tabulated numbers that often included errors.
One of the first innovations was a site that debuted in 1997 called commissioner.com (now owned by CBS Sportsline).
"It was great having daily updates and stats you could trust," Bleckman said. "It helped with roster moves because information was more available. You had to read [the] paper before."
Berry said one thing that makes fantasy games popular is that the winners get to feel like experts.
"I guess I like to think that there is some skill involved," said Jonathan Kelly, who won two fantasy football and one baseball league within the past year. Kelly, a 28-year-old software engineer, admitted that there is also an element of luck (players staying injury free, others getting more playing time than expected) in winning three leagues.
"But there is a big part of preparation and knowing what to look for and how to approach a draft," he added.
In a few weeks, when the season gets going on the weekend of September 9, Kelly will head over to a friend's house and watch the NFL games while his son plays with his friend's children. Forman and Bleckman, the transplanted Pittsburghers, each go to a bar in their new towns to watch the Steelers game.
The three will root on their hometown teams, all the while scanning other games and taking note of how certain other players are doing.
Just watching their fantasy players and dreaming of a title. E-mail to a friend
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