It's clear that Facebook and other social networks are all the rage these days. Millions are enjoying interacting with friends and potential friends on them -- and companies are establishing presences on them as well. It's easy to roll our eyes and wax cynical, wondering who would really want to "friend" their local supermarket or shoe store -- but it's actually turning out to be a win-win situation for consumers and companies. 

According to the research organization Compete: "One quarter of consumers now visit an official Facebook page for a retailer or consumer product at least once a month. And more than half of these respondents (56%) say they use retailers' Facebook pages to keep up to date on sales and promotions."

Facebook pages have influenced more than 20% of consumers in their purchasing decisions, and close to half of consumers surveyed follow five or more retailers or brands on Facebook.

What the cool kids are doing
Smart companies, then, would do well to look into how they might make the most of the medium. Here's what some of the most popular Facebook brand pages are doing.

  • The Ford (NYSE: F) Facebook page sports about 750,000 followers, considerably more than General Motors' (NYSE: GM) 272,000. On the page you'll see Ford sharing links to articles of general interest (such as Baby Boomer trends), reporting on its improvements in auto safety, and inviting fans to live chats with its management. Among fans posting on the page, you'll find folks posting photos of Ford cars they admire and thanking Ford for supporting various charities. All such posts are likely to boost the company's reputation
  • Research In Motion's (Nasdaq: RIMM) BlackBerry page has more than 7 million fans, and its Info page has gobs of links to sites of interest, such as its YouTube and Twitter homes and various customer-support channels. On its Wall, the company has started discussions about favorite summer apps (with more than 500 responses) and explains how easy it is to trade up to a fancier BlackBerry. The company also engages its fans with trivia questions, answerable through BlackBerry searches.
  • The Apple (Nasdaq: AAPL) iTunes Facebook page sports almost 16 million fans and actually gets more unique visitors than the iTunes website itself! On its various sub-pages, Apple lists top songs, movies, apps, and TV shows and extends some special offers exclusive to its Facebook fans. Fans are encouraged to share their favorite songs with their friends, which will boost business for the store. On the Wall, you'll find posts such as one offering three free episodes of the "Shark Week" programming on Discovery Communications' (Nasdaq: DISCK) Discovery Channel, as well as links to children's books in the iBookstore. Fans can also download, for free, full performances by popular artists such as Adele.
  • The Best Buy (NYSE: BBY) Facebook page has more than 3 million fans and engages them in all kinds of discussions, such as the strangest things that have gone through washing machines (a passport, a snake, a remote-control device, and a not-yet-offered engagement ring). Best Buy also offers invitations to events at various stores. In a win-win arrangement with Microsoft (Nasdaq: MSFT), the page recently promoted Kinect devices and invited fans to share what they like most about it.

Facebook offers companies a powerful way to interact with consumers and promote their business. Most people won't think or remember to visit the various websites of companies whose offerings they like, but by becoming a Facebook fan, they can more easily access content from such companies. What effective companies need to do is give consumers a reason to pay attention, such as by delivering special deals, news, reviews, information, or simply entertainment. That, in turn, can deliver more sales and profits.

As you scour the market for the most compelling stocks, consider checking out a company's social media presence, to see how it's engaging with consumers.

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Longtime Fool contributor Selena Maranjian owns shares of Ford, Apple, and Microsoft, but she holds no other position in any company mentioned. Check out her holdings and a short bio. The Motley Fool owns shares of Ford, Apple, Microsoft, and Best Buy. Motley Fool newsletter services have recommended buying shares of Discovery Communications, Apple, Ford, Microsoft, Best Buy, and General Motors; creating a bull call spread position on Apple; and creating a diagonal call position in Microsoft. Motley Fool newsletter services formerly recommended Best Buy. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.