You've heard about Twitter -- that curious, strangely addictive social-networking technology that facilitates torrents of truncated messages among millions of users. You might even know your hashtags from your re-tweets. But how can you make money with it?

Forbes canvassed scads of businesses and pricey social-networking gurus looking for honest answers. Admittedly, we were skeptical. After all, how much can you accomplish in 140 characters or less?

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Turns out there are myriad ways Twitter can have an impact, and not just as a marginal marketing tool. Indeed, we found 21 clever ways to use Twitter -- for everything from boosting sales and scouting talent, to conducting market research and raising capital. Chances are, there will be many more.

"I believe Twitter is a communication platform," says Nathan Egan, founder of Freesource Agency, a social-networking consultancy in Philadelphia. "In a year or two, everyone will be on it, using it in totally new ways."

Better yet, getting results "doesn't take a year or six months, but a matter of weeks," adds Mark Schaefer, head of Schaefer Marketing Solutions in Knoxville, Tenn.

Some strategies take more time, or are more industry-specific, than others. Taken together, though, this collection of techniques and real-world examples constitutes a powerful online arsenal for companies large and small. Herewith, some highlights:

Coupon Campaigns

Congratulations for getting to the end of this sentence. "As an online culture, people are not reading; they're scanning," says Dell Computer's Stefanie Nelson, voice of @DellOutlet. "The shorter and more direct your message is, the more successful you're going to be." Dell tweets links to coupons at Dell Outlet's Facebook page, which shoppers use during checkout at Dell.com.

This strategy works for small companies, too: The abbreviated offers are easy to produce--you don't need an ad agency to write 140 characters. California Tortilla, a chain of 39 causal Mexican restaurants based in Rockville, Md., spread coupon "passwords"-- through its Twitter feed @caltort -- that must be spoken at checkout to be redeemed.

Viral Marketing

In July, in honor of its 10th birthday, London-based do-it-yourself Web site builder Moonfruit gave away 11 Macbook Pro computers and 10 iPod Touches. Contestants had to tweet using the hashtag #moonfruit. (Hashtags collate Twitter responses.) Nearly a month after the contest ended, traffic to Moonfruit's Web site is up 300%. Sales are up 20% this month, more than paying off the $15,000 investment. And the Moonfruit Web site has climbed onto the first Google page for "free website builder" (it used to be on the fourth).

Word to the wise, says Moonfruit founder Wendy White: Such campaigns must be courteous and fit with a company's brand, lest you draw the ire of the Twitter-sphere: "There's a fine line between annoying people and getting the thumbs up."

Artful Customer Service

Frank Eliason, director of digital care at Comcast, uses Twitter to help 200 to 300 subscribers a day with issues ranging from sporadic Internet service to errant e-mails. Frank and his team receive direct questions at the @comcastcares account and search for complaints. Twitter has a built-in search, but it's more efficient to set up a permanent search on one of the free, third-party Twitter applications, such as TweetDeck.

Eliason's key to success: maintaining friendly relationships, not foisting unwanted advice. "If they want assistance, they'll let me know," he says. Eliason has a 10-person help desk at his disposal, but small businesses can use Twitter to provide better customer service, too. Even a little help goes a long way.

Focus Groups

Back in the old days (last year), companies actually paid customers to solicit their opinions. There were 3.37 million mentions of Starbucks on Twitter through early May 2009, and all of that information is available for less than the cost of a frappucino. "There is a major element of Twitter that's about listening and learning," says Brad Nelson, the man behind @Starbucks. "Twitter is a leading indicator." Collecting the information is as simple as searching for references to your company.

Morgan Johnston, manager of Corporate Communications at Jet Blue, abolished a $50 fee for carry-on bikes after hearing complaints via Twitter. "Think of Twitter as the canary in the coal mine," says Johnston. "We watch for customers' discussions about amenities we have, and what they'd like to see made better." For a more formal approach, lob a simple post asking for feedback and provide a hashtag to collect the responses.

Poaching Customers

"Twitter is not just a kid story," says Chris Brogan, president of New Marketing Labs. Brogan should know: He is one of several Twitter experts advising companies on how to spy on their competition and to swoop in with a better service or discount.

Freesource's Egan describes how to do it: Using TweetDeck, set up a permanent search for all permutations of your competitor's name, as well as words that convey dissatisfaction ("sucks" or "hate"). Public replies to those new prospects are dangerous, as your competition may see them, so the best bet is to follow them and get followed back, allowing you to send direct messages.

Customer Expectation Management

Bad things happen--it's how you condition customers to deal with it that counts. Jet Blue tweets flight delays. In April, when a Stanley Cup broadcast was interrupted, cable provider Comcast used Twitter to immediately inform its subscribers that the culprit was a lightning storm, and that transmission would soon be restored.

Small companies -- like United Linen, a linens and uniform company in Bartlesville, Okla.--can manage expectations this way, too. When a major snowstorm hit the area, Marketing Director Scott Townsend used Twitter to let customers know deliveries would be delayed. "It was a great way to send information to everyone," he says. "They understood we wouldn't be there, but they wanted to know what our status was and updates as the situation changed."

Corralling Eyeballs

During last year's NBA Eastern Conference Finals between the Cleveland Cavaliers and the Orlando Magic, Turner Broadcasting managed to weave social-media feeds into its home page. Fans accessed the conversation by logging onto Twitter through TNT.com, and the tweets were also posted on Twitter with links back to TNT.com. Those forums mean more Web traffic -- and thus more advertising revenue. "It's exciting to sell this to an advertiser," said Liza Hausman, vice president of marketing for Gigya Socialize, the brains behind the integration technology.

Vendor Selection

Twitter can snag customers, but how about suppliers? Crowdspring, an online marketplace that marries businesses with graphic designers (see "The Creativity Of Crowds "), used Twitter to build up its stable of contributors--now 12,000 strong globally.

Business travelers can apply this same logic: Tweeting that you're about to visit a city can scare up discount offers from hotels, bus companies and other travel-services providers.

Conflict Resolution

Wiggly Wigglers, a Herfordshire, U.K.-based marketer of gardening and farming supplies, was recently overcharged $10,500 by British Telecom. Five months passed without restitution.

Finally, Wiggly owner Heather Gorringe hit the Twitter-sphere, asking if anyone else had had problems with BT. @BTCare sent Gorringe a message within 30 minutes promising help; two days later, the bill was amended. "When I phone them up, I'm an isolated call to deal with, so I'm less important," says Gorringe. "But if I tweet, and 1,193 people re-tweet, 100,000 people see it within 30 seconds."

Employee Recruitment

Sodexo, a food services and facilities management company, trains its recruiters on Twitter and other social media. An automated program sends prospects a direct message whenever a position opens up, and the messages are opened 30% of the time.

The trick, says Arie Ball, vice president of talent acquisition at Sodexo, is to be as personal and engaging as possible: "People get an insider's view, a sense if this is a company they want to work for." The company says that using Twitter as a recruitment tool has helped cut its investment in online job boards by hundreds of thousands of dollars.

Raising Capital

As in the physical world, no one likes to be solicited for contributions online. A better Twitter tack: Don't ask, just inform.

Last Thanksgiving, Epic Change, a nonprofit that encourages people to tell their stories to transform communities, launched the Tweetsgiving Web site, with the help of theKbuzz, a word-of-mouth marketing firm. Tweetsgiving asked people to tweet what they were grateful for, and compiled the responses at #tweetsgiving, with a link back to the Tweetsgiving site, where users had the option of contributing money to build classrooms in Tanzania.

Over the 48-hour campaign, 15,000 people came to the Tweetsgiving site; 360 donated, for a total of $11,000. "We never asked people to give," says Stacey Monk, founder of Epic Change. "We got people invested in their own, personalized way."