"Whatup Twit-talkers! I have a couple of complete skateboards to give away today. Stay tuned… First one is for 760 locals: Palomar Oaks Way just south of Palomar Airport Rd. Look behind the fire hydrant just across the bridge. Go now."

The message popped up on KT Alach's cell phone on a morning in late March. The sender was global skateboarding icon and Carlsbad resident Tony Hawk. It wasn't a private note, mind you, but rather a tweet, transmitted to the hundreds of thousands of followers of Hawk's Twitter account.

Alach doesn't care about skateboarding; she only learned of Hawk's Twitter page through a coworker. But the board was stashed just a few minutes away from her office in Carlsbad, so she figured, what the heck? Within a half-hour, the 24-year-old Alach had found the skate deck -- autographed by Hawk -- in the designated location and tweeted a photo of herself holding the prize as proof of her discovery.

Duly intrigued by the possibilities, Hawk set into motion a plan for a wide-scale, Twitter-driven scavenger hunt on Easter -- but for skateboards instead of eggs. Enlisting the help of friends, business associates and even family members, he hid 60 boards across 10 states and three countries. Throughout Easter day, he revealed clues as to their location via Twitter. He personally hid the last two in what he called "meaningful" spots in the San Diego area.

"I had to scan through replies to figure out which ones had been located, and it was overwhelming the amount of chatter that came through," Hawk wrote in an e-mail. "Mostly people were thanking me for doing it. At one point, I had nearly hundreds of messages loaded on my screen…

"It was much more exciting than I anticipated because people liked to 'watch' from Twitter almost as much as they liked physically searching."

To convey an idea of the runaway growth of Twitter -- the social networking Web site that is most easily described as micro-blogging, in which users are supposed to answer the question "What are you doing?" in 140 characters or fewer -- Hawk, at the time of the Easter hunt last month, had about 300,000 people following him on Twitter.com (user name: tonyhawk). As of Saturday afternoon, in part because of the attention generated by the hunt, that number had more than doubled to 610,109.

That's a population approximately the size of Boston peering into Hawk's day-to-day life, in all its excitement and minutiae. If that sounds excessive or somehow ridiculous, then you haven't been indoctrinated into the universe of Twitter, a strange realm where celebrities mingle with common folk and the English language is bastardized 140 characters at a time.

Twitter was founded in 2007 -- long after social media counterparts like Facebook, MySpace and YouTube -- but it has taken only two years for the site to shoot into the stratosphere of cultural relevancy. And its footprint has become particularly large in sports, with athletes, coaches, teams and leagues getting swept up in the craze.

Some of the most prominent sports figures in the world are on Twitter, including Hawk, Shaquille O'Neal (THE_REAL_SHAQ; 935,261 followers), Lance Armstrong (lancearmstrong; 812,012), Serena Williams (serenajwilliams; 113,359), CC Sabathia (CC_Sabathia; 10,908), Pete Carroll (PeteCarroll; 17,675) and Shawne Merriman (shawnemerriman; 3,998).

"I was talking to Puff Daddy, and he was like, 'Man, you got to get on this Twitter,' " said Merriman, the Chargers' Pro Bowl outside linebacker, who started his page only 2 1/2 weeks ago.

Many professional sports teams -- the Chargers among them -- have developed Twitter sites to keep fans abreast of the latest news, as have the NFL and NBA. The NHL league office isn't on board yet, but commissioner Gary Bettman (Commish_Gary; 847) is, along with NFL chief Roger Goodell (nflcommish; 5,352). What are you waiting for, Bud Selig?

Desperate to court fans as a start-up league in a brutal economy, the new Women' s Professional Soccer took Twitter usage to another level, allowing certain players to send out tweets before, after and even during games (the "during" messages, thankfully, are limited to players sitting on the bench).

Virtually everyone in sports, it seems, is on Twitter for one reason or another. And if your favorite athlete or team hasn't caught the bug yet, well, just wait five minutes.

"Twitter is the perfect complement to sports, I think," said Bill Handy (billhandy; 1,232), an Oklahoma State professor who teaches a course on social media, including Twitter. "If you really are dedicated to your fans, if you really want to talk to them, this is the perfect tool. It doesn't get any better than this."

"Whoa! They just came to my room and said our truck was broken into and someone stole my time trial bike! Wtf?!? APB out to the twitterati."

It was the tweet heard 'round the Twittersphere. When Armstrong discovered that his custom-made Trek bike had been stolen the day after the first stage of the Tour of California in mid-February, he not only alerted the Sacramento police, he also informed his Twitter followers, who at the time numbered about 140,000.

Armstrong later posted a picture of the distinctive bike and offered a reward for its return, and the Twitter buzz spawned a Facebook group called "1 Million Citizens Looking for Lance Armstrong's Stolen Bike." By the time the bike was found a few days later, police admitted that the online campaigns had aided in their search.

Perhaps nobody in the sports world has taken to Twitter quite like Armstrong. From joining the site just last November, he has developed a cult following that trails only O'Neal among sports figures and ranks with the New York Times (nytimes; 823,467) and Al Gore (algore; 762,613) among all Twitter sites.

Armstrong updates his page a head-spinning number of times per day, and the bike episode was not the last time he used Twitter to bypass traditional media and break news directly to his fans. He also did so after he broke his collarbone during a race in Spain in late March.

Armstrong clearly enjoys Twitter, but he has spoken of other motivations for signing up: his desire to spread the word about his efforts to raise awareness for cancer research, and his compulsion to be as transparent as possible given ever-present suspicions of performance-enhancing drug use.

"You talk about doping, and doping in sport -- the most important thing is the whereabouts," Armstrong said in February after the Tour of California ended in Escondido. "All you've got to do is look at my Twitter. I mean, every hour you know exactly where I am."

Armstrong may have high-minded reasons for Twittering, but for Shaq, it's just another outlet for his larger-than-life personality. His user name is a nod to the numerous fake pages out there (we're looking at you, Kobe Bryant and Eli Manning), his location is listed as "PHOENIX/EVERYWHERE," and his bio reveals that he's "VERY QUOTATIOUS, I PERFORM RANDOM ACTS OF SHAQNESS."

A sample tweet from last week shows O'Neal in his chat-speak, stream-of-consciousness brilliance and helps explain why he'll soon be the first athlete to surpass one million followers:

"Its so hot n phoenix, I just saw the devil at the airport, I asked him were he was goin, he said I'm gettin the hell outta here."

As O'Neal told the Associated Press recently, "I'm a regular guy. I shop at Wal-Mart. I try to do the same things so-called regular people do. I know when they see some of my comments, they know that I'm as funny as I seem."

Merriman said he had been hearing of Twitter for about six months before finally taking the plunge at the behest of his rapper friend Sean Combs (iamdiddy; 856,645). Already the type whose BlackBerry is tied to his hip, Merriman now updates his feed obsessively. Besides promoting various media appearances and business ventures (like many celebrity Twitter users do), he employs Twitter as a window into his maniacal workout regimen as he continues on the road back from knee surgery last fall.

"People need to know on a daily basis more about what I'm doing because a lot goes into what I do, and what (NFL players) do," Merriman said. "One time I put on there that I couldn't sleep so I got up and worked out at 10:30. When people see that, they're like, 'Damn, he works out at 10:30 at night sometimes?' Yeah, I do."

Pro teams and leagues have devised creative ways to use Twitter as a promotional and marketing arm. On the opening night of the Stanley Cup playoffs in mid-April, the NHL helped organize 23 "tweetups" (essentially a viewing party for Twitter users) in 23 cities across the United States and Canada. The Portland Trail Blazers, who lived up to their nickname by starting a Twitter site back in 2007, had Twitter partly to thank for a downtown playoffs rally last month that reportedly drew more than 10,000 fans.

Even the big, bad NFL -- which needs more publicity like actor Ashton Kutcher (aplusk; 1,674,930) needs more Twitter followers -- has gotten into the act. Several teams, including the Chargers, used Twitter to announce picks at last month's draft, in some cases before Goodell had reached the podium in New York City.

"The way I look at it is, if you're not watching the draft, if you're on the golf course or at a baseball game, you still can know exactly what's going on," said Jim Steeg, the Chargers' executive vice president and chief operating officer, who typed the tweets himself on draft day. "I think the instantaneous nature of it is nice.

"You want to make fans feel like they're part of the process and not just reading it in the paper the next day. It's like they have some sort of insider knowledge."

"Happy cinco de mayo! I'm celebrating at the pac10 coaches mtg in phoenix- How are YOU celebrating the day?"

If you ever doubt that Carroll has more fun than a grown man in a high-pressure job has any right to have, just sign up for his Twitter feed. The USC football coach punctuates thoughts with exclamation points as if he earns royalties on them, and he's engaged in an ongoing campaign to attract actor, and USC graduate, Will Ferrell to Twitter (at last check, Ferrell has a page of dubious authenticity).

Life is one long day at the beach for Carroll, but his presence on Twitter is not entirely frivolous. Carroll stands at the forefront of an increasing number of college coaches using the site as a recruiting tool.

After the NCAA banned text messaging two years ago, coaches needed a new way to reach out to high school stars on their wavelength (read: on their cell phones). Along came Twitter and -- voila! -- football coaches like Notre Dame's Charlie Weis (NDHFC; 3,222), LSU's Les Miles (LSUCoachMiles; 2,841) and Washington's Steve Sarkisian (CoachSark; 3,320), and basketball coaches like Kentucky's John Calipari (UKCoachCalipari; 19,362) and Indiana's Tom Crean (TomCrean; 4,552) jumped on the bandwagon without shame.

Miles went so far recently as to announce that he'll tweet -- through a staff assistant -- before, at halftime of and after games this fall.

"Absolutely, it's for recruiting purposes," Miles told USA Today. "It allows us to communicate, to those people that subscribe, blasts of information. … It's also an opportunity for those prospects that subscribe to communicate to us."

With any new communication tool, however, comes a potential land mine with regard to NCAA rules. The NCAA, in fact, was compelled to supplement its bylaw concerning electronic transmissions with the dos and don'ts of Twitter. Essentially, because they function as blog updates, tweets by coaches are permissible -- as long as they are sent en masse and not to individual prospects.

Tweeting to the world about Cinco de Mayo celebrations, therefore, is fair game.

"Scottsdale is fun. The over aggressive males are not. does every dude think they can fight? they sure have some confident mouths out here!"

So read the tweet of San Francisco Giants closer Brian Wilson near the midnight hour on April 25. The tweet, though, no longer exists. Neither does Wilson's Twitter account, which he canceled two days later in the wake of a bizarre, only-on-the-Internet controversy.

The afternoon following his apparent escapades in Scottsdale, Wilson blew his first save of the season in a loss to Arizona. A Giants beat writer and members of the blogosphere -- having noticed Wilson's tweet and others like it -- attempted to draw a connection between his night on the town and his performance the next day.

Wilson promptly removed the posts in question, replacing them with a disclaimer: "WARNING-do not take my twitters seriously, they are made up stories that reflect my humor." Asked by reporters to clarify, Wilson said he jokingly sent the messages from the comfort of his hotel room. He then took down the site altogether.

"This Twitter crap, I've obviously got to stop because people are taking it too serious," Wilson told the San Jose Mercury News. "… Obviously, it's my fault for making up a bunch of stuff, but I know for a fact most of those followers know I'm not being serious."

Wilson learned the hard way what others had discovered before him -- the seemingly harmless observations that sports figures make on Twitter can have very real repercussions.

Milwaukee Bucks forward Charlie Villanueva (CV31; 24,883) caused unintended waves when he sent a tweet at halftime of a game against the Boston Celtics on March 15. The message was simply about the need to improve his play in the second half, but it was enough to draw the ire of coach Scott Skiles, who reprimanded Villanueva for what he considered a lack of proper focus.

Villanueva agreed to stop the practice, but he couldn't help pondering the issue further on Twitter: "About to take my nap, but I'm looking for some answers here. what's the difference between halftime twitting and halftime interview?"

Notorious for criticizing NBA referees, Dallas Mavericks owner Mark Cuban (mcuban; 36,573) found out that there's no difference between ripping them on Twitter as opposed to through the media. After lodging complaints on his site following a March 27 loss to Denver, Cuban was fined $25,000 by the league. Like Villanueva, Cuban later got philosophical, wondering in a blog post whether tweets are copyrighted.

"The main thing people need to understand is that everything you say in a public forum is open for redistribution," said Handy, the Oklahoma State professor. "If you say something on Twitter, the assumption is you're doing so knowing full well that people may copy the text and repeat it to other people. If you want your comments to stay private, my recommendation is don't say them at all."

Merriman hasn't written anything to put himself in hot water -- he actually praised the Chargers' first-round selection of Larry English, a fellow outside linebacker, in the draft -- but he understands the dangers.

"People are watching," he said. "When we got English, I wrote 'Let's bring the heat,' and that was on ESPN the next morning. You have to watch what you write. But at the same time, it shows that you're human and you do human things."

"Bonjour! 600k = "Oprah rich" Thanks for all of the support, it's been a blast watching Twitter blow up so quickly"

Hawk rocketed past 600,000 followers on Friday. In a matter of weeks, he'll probably join Shaq in the exclusive million club.

Not so long ago, Twitter didn't even exist. Now, you can hardly escape it. In five years, will baseball players be tweeting in the dugout during games? Will Goodell himself be announcing draft picks on Twitter before he reaches the podium?

Or is this all one giant fad, to be superseded by the next social networking phenomenon?

Who knows? But we'll be watching -- 140 characters at a time.