In 2013, buying a single 30-second commercial spot during Super Bowl XLVII cost advertisers an average of $3.5 million -- and yet, the single most-talked about advertisement from Sunday night didn’t cost a dime.

At approximately 8:48 p.m. EST, Oreo capitalized on a 34-minute power outage in the middle of the third quarter between the Ravens and the 49ers with a single advertisement:

“Power out? No problem.” Oreo wrote on its Facebook and Twitter pages. The company also attached a dark photo with a single spotlight on an Oreo cookie. “You can still dunk in the dark,” the Oreo caption said.

Oreo’s advertisement was the most-talked about piece of marketing the entire night, racking up more than 12,000 retweets, as well as 20,000 Likes and more than 6,000 shares on Facebook.

Twitter user Rolando Ugarte perhaps said it best“The lights went out and a new era in advertising was born,” he wrote, adding the hashtag “#JustInTimeAdvertising.”

What Did Oreo Do So Right?

Most Super Bowl ads were conceptualized well ahead of time. Marketing experts sit around tables dreaming up various scenarios for attracting millions of eyes with a single commercial; unfortunately, no expert could have predicted that Monday’s water cooler discussion would revolve around a blackout that lasted more than a half-hour, delaying the most important football game of the year.

New York City-based marketing firm 360i, which worked with Oreo to help the cookie company celebrate its 100th birthday, also worked with Oreo during last night’s Super Bowl. In a brief interview with Buzzfeed, 360i President Sarah Hofstetter said that the Oreo blackout ad, while improvisation, was largely a result of great preparation.

"We had a mission control set up at our office with the brand and 360i, and, when the blackout happened, the team looked at it as an opportunity," Hofstetter said. "Because the brand team was there, it was easy to get approvals and get it up in minutes."

Things “got fun” when the Super Bowl game went off script during the blackout, but Hofstetter said the real key was having executives from Oreo in the “mission control” office with them.

"You need a brave brand to approve content that quickly,” Hofstetter said. “When all of the stakeholders come together so quickly, you've got magic."

Oreo also paid for a 30-second ad during last night’s game, which featured an epic “Whisper Fight” in a library. That video has racked up more than 430,000 views on YouTube thus far. While that commercial is still very successful in its own right, it’s likely that Oreo’s blackout ad was significantly more effective, reaching many more people through word of mouth than its multimillion-dollar ad spot.

Is The Future Of Advertising Free?

Companies have been finding a great deal of success by focusing on digital media, rather than traditional media like TV. Digital media is not free -- nothing is -- but it’s certainly cheaper and potentially more effective: Mattel, Ford and Kodak are all excellent case studies for any company considering greater investment in digital and social media marketing.

Oreo proved it again last night: Digital is not only cheaper, but it’s more flexible, which is important these days, during which the speed at which information travels really does matter. An advertisement making light of last night’s Super Bowl blackout would be completely ineffective after the fact, or even the next day; thanks to a focus on digital preparedness, Oreo was able to jump on the biggest news of the Super Bowl, which was an entirely unexpected story line.

Focusing on digital and social is always the right move, particularly for companies that can quickly pivot to changing environments like the one last night, but it’s more than just existing on the platform. As Oreo proved, companies are most successful when they’re listening, particularly to what their fans are saying. Social media gives companies a great opportunity to “Go Where Your Fans Are”; by adapting and molding their content to the fans, Oreo made a mark that was not only significantly more effective than million-dollar TV spots, but more personal too. Just “going digital” isn’t enough; it must be embraced.

Bonin Bough, VP of global media and consumer engagement at Mondelez, Oreo’s parent company, preempted Oreo’s big night in his pregame story: “It’s About Not Just The Creative But How Creatively You Use It.”