If the feel-good corporate message of the 1970s was to inspire us to do something nice, like to buy the world a Coke, what then could we accomplish, with a little benevolent prodding from a major brand, today in this era of social networking and virtual movements?

How about pitching in to pay for yoga classes for trauma victims in Manhattan, or, to donate diapers to impoverished new parents in Detroit? There are 729 such ideas, some as simple as building a community garden in the hopes of introducing some fresh veg to protein-deprived inner city kids or to host a prom for senior citizens in a place called Cabarrus County. The catalyst behind this effort, called the Refresh Project, is PepsiCo, which has pledged to deliver $20 million in grants to fund local projects and causes voted on by you as the most deserving.

There are lots of ideas (the virtual suggestion box maxed out in a few days; a new round begins next month), and lots of support too; over 340,000 people have signed up to the Pepsi Refresh Project on Facebook since it went live.

The Refresh Project is being called the biggest ever social media campaign of its kind, a description that doesn’t sit well with Pepsi itself. “The Refresh Project is not a social media project,” Bonin Bough, global director of digital and social media at PepsiCo, corrects me. “Social media happens to be one of the communication channels at the heart of this social engagement effort. It is the mechanism we are using to demonstrate the power of the individual, and individual ideas.”

The concept of funding community initiatives is at the heart of Pepsi’s philosophy under CEO Indra Nooyi, one that focuses a good deal more on corporate and social responsibility, not to mention sustainability issues, than any of her predecessors. “We realize ‘local’ is often overlooked,” Bough explains. And so the idea of betting big on social media, and relying on the public to develop something socially worthwhile, has won support from the CEO on down.

But so far, Pepsi is generating more attention for what it’s not doing with this campaign. The company has decided not to publicize The Refresh Project during Sunday’s Super Bowl. It marks the first time in 23 years the company is passing on the big game, choosing to instead bank the $2.8 million out-of-pocket expense advertisers must pony up this year for a 30-second spot. (PepsiCo’s Doritos is scheduled to run three commercials, each inspired by Doritos’ fans.) Skeptics point out it may just be cheaper for Pepsi to play the role of do-gooder. Fast Company calculates the company “spent $33 million on Super Bowl advertising last year, and the Refresh Project will cost $20 million.”

That’s missing the point, says Bough. It’s hard to explain in 30 seconds the spirit, not to mention the where and how, of a civic-minded project like this. “This project is about creating a movement, not a moment,” he says. To that end, PepsiCo, an NFL sponsor, has recruited stars Drew Brees, Mark Sanchez and DeMarcus Ware to promote the effort on the much-trafficked NFL.com throughout the week. Aside from the Facebook page and the company’s Twitter feed, PepsiCo has also built a blog, with appointed “ambassadors” such as New York Times columnist Allison Arieff, an expert in functional design, and Rebecca McQuigg Rigal, formerly of Creative Artist Agency, who blogs about art and culture, to inspire us. It’s also partnered with GOOD, DoSomething.org and Global Giving to vet submissions worthy of the public vote.

As with any effort inspired by, and for the benefit of, the public there is always some awkward moments for management. America’s pet causes run from the wacky to the way-out controversial. To that end, there is a long list of off-limits topics that Pepsi has drawn up. For example, one disclaimer reads: “Use common sense. Don’t promote or suggest legalization of alcohol, tobacco, firearms & weapons, drugs or pornography. Don’t suggest the taking up of arms. Don’t challenge current laws, promote treason or terrorism and especially don’t suggest overthrowing the government.”

So far, so good. Of the 748 ideas under consideration in Round 1, the top vote-getter is the suggestion to send Girl Scout cookies to the troops overseas. Nobody has yet, as far as we can see from the leader board, suggested something under the “health” category like removing sugary soft drinks from the vending machines of all public schools. Nor has anyone suggested a community drive to ban bottled water, a fitting idea perhaps for “The Planet” sub-section.

Bough says Project Refresh won’t back down if ideas like these are voted through by the public. There’s no sense in sticking your head in the sand, he says, adding, “the public is already having these discussions, whether or not it is occurring on the site or not. Part of our obligation is to participate in these issues that they care about.”

Refreshing, indeed.