Give salesforce.com (NYSE: CRM) credit for being inventive. Last night, cloud computing's poster child rolled out a public version of its Chatter social network in two Super Bowl ads featuring the game's halftime stars, The Black Eyed Peas.

The ads themselves didn't say much, referring only to broad claims of allowing teams to do "impossible things" together. That's a good sound bite, but it doesn't reflect what salesforce.com is trying to do with Chatter.

Put simply, it's a private room for company employees to share links, photos, files, thoughts, etc. Think of it as a specialized form of Twitter or Facebook that's one part meeting room, one part water cooler, and one part whiteboard.

Interestingly, this isn't a new idea. Yammer has been providing much of the same functionality since the company's founding in September of 2008. So much so that Yammer recently created a video in which it amusingly tags salesforce.com CEO Marc Benioff as a "copycat."

The skewering refers back to Yammer's debut at the TechCrunch50 competition two years ago. Benioff, a judge, is quoted in the video as saying he'd invest in Yammer and that he could see salesforce.com buying the product. Cookie jar, meet hand.

So far, I've only seen demos of Chatter. But I'm a regular user of Yammer -- The Motley Fool pays for the service -- and I can see the parallels. All the reasons salesforce.com lists for adopting Chatter apply equally to Yammer.

And I'm not the only one who thinks so. In a December interview with TechCrunch founder Michael Arrington, Yammer CEO and founder David Sacks said his company is on track to generate $10 million in 2011 revenue from a list of more than 1,000 paying clients, including Cisco (Nasdaq: CSCO), Alcatel-Lucent (NYSE: ALU), and us Fools.

Knowing all this, I've got to wonder why Benioff didn't simply buy Yammer. He's right; Chatter-Yammer is exactly what salesforce.com should offer customers. At Yammer's $10 million run rate, salesforce.com probably could have struck a deal for anywhere between $50 and $100 million in cash -- peanuts when you consider salesforce.com had more than $750 million in cash and short-term investments as of Oct. 31.

We don't know why Benioff chose to build rather than buy. Yammer may have rebuffed offers. Or maybe salesforce.com wanted a platform designed from the ground up to work with its Apex programming language and Force.com platform.

Either way, I'm expecting more of these types of add-ons as salesforce.com grows out of its historic niche as a supplier of online sales support tools into a provider of business software available online. The yin to NetSuite's (NYSE: N) yang, you might say.

But as the guy who recommended our Motley Fool Rule Breakers subscribers buy shares of salesforce.com, I also don't want to guess. So, earlier today I sent an email to Benioff asking about Yammer and his overall strategy for creating value at salesforce.com. If he responds, you'll see it here first.

In the meantime, tell us what you think about salesforce.com, its Super Bowl ads, Chatter, and Yammer using the comments box below. You can also rate salesforce.com in Motley Fool CAPS.

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