Jennifer Wright built a better pizza box and found a better way to spread the news.

She told Ashton Kutcher.

Four minutes after she tweeted the actor, he responded with a short and sweet “smart.” The most-followed man on Twitter put Wright on the radar of his 1.3 million followers, who took the idea viral. The day after their exchange, Green Box had 20,000 hits on its site. Now, its YouTube video boasts more than 700,000 views.

Wright’s success in raising the profile of Green Box, a biodegradable pizza box that breaks down into plates and a handy storage container that fits into most refrigerators, is just one example of the reach social media have. With platforms such as Twitter, Facebook, LinkedIn, YouTube, and others, ideas can—occasionally—make a big splash without huge budgets.

Businesses of all stripes are exploring ways to use social media to reach the coveted 18-to-35-year-old population, get ahead of the competition, stay abreast of trends, and grow their business. In some cases, it's working. When household-products giant Procter & Gamble wanted to test how it’s new Bounce Bar would do in sales, it used Vocalpoint.com to reach out directly (and inexpensively) to moms for feedback. JetBlue has gotten high marks from fliers like Dave Raffaele, who wrote a blog post on how the value airline “used Twitter to treat me like a human.”

But success is not a given. And as companies plow into this new realm, it’s no wonder that the business of helping businesses use social media has flourished.

Who uses what:

Twitter:

• Typical user: 18-to-49-year-olds, 55 percent female, 45 percent male, half are college-educated, and most earn $60,000 or less per year
• One of the fastest-growing social-media platforms
• More than 22 million monthly visitors

Facebook:

• Typical user: 12-to-34-year-olds, 54 percent female, 46 percent male, 42 percent are college graduates who make $60,000 to $100,000 or more per year
• Just surpassed MySpace as No. 1 social-media network
• 91.2 million users in the U.S., with an additional 100 million global users

LinkedIn:

• Typical user: 35-to-50-year-old (and older) males, predominantly college-educated, earning at least $60,000 per year
• Executives from all Fortune 500 companies are members
• More than 42 million members in 200 countries

*Sources: Quantcast.com (May 2009 data), New York Times, Maven Communications

As more companies embrace social media, existing platforms are adding on functionalities to serve their needs. You can now find entertainment job listings on MySpace, Facebook users are banding together to qualify for group shopping discounts. And LinkedIn has evolved from being only about jobs. A.J Garritson, co-founding partner of Boston-based 451 Marketing, says the site—which now boasts more than 42 million members—is a go-to source for working professionals. “It’s a place for executives to get career development from their peers and higher-ups.”

The demand for social-media expertise is also growing quickly. More and more firms understand that in order to resonate with their clients, they can’t just rely on young interns to mind their outreach strategies, says Richard Laermer, author of Punk Marketing: Get Off Your Ass and Join the Revolution and CEO of RLM PR in New York. Instead, they are even hiring or seeking to hire social-media executives. Jake Wengroff, global director of corporate communications for Frost & Sullivan in Mountain View, California, says companies aren’t just looking for writers to compose blog posts. Implementing new policies and guidelines, companies are looking for human resources personnel that can educate their staff about how to do social media right (and wrong).

A simple search on Amazon brings back nearly 40,000 titles on social media. Countless companies have created "webinars", primers and tools to help the business world take advantage of all the offerings. Top universities, including Columbia, Stanford, American, and Harvard now offer classes on utilizing the platforms as part of their marketing and MBA programs.