I’ve been loosely following the clean-water space since 2005 now, and have never been as intrigued by an opportunity as with WaterForward. In short, it’s an online social project run by Michael Birch to engage the crowds to donate more to charity:water, which builds clean-water wells in Africa, India, and LatAm.

The basic economics of charity:water (and others like blood:water) is that $1 you donate can provide 1 person in a developing nation with clean water for 1 year. Looking at it from another angle, every dollar invested yields $12 in direct and indirect economic impact, as clean water has effects on education, agriculture, healthcare costs, etc.

WaterForward, though, is a spin off the age-old pay-it-forward concept and porting it to trackable, charitable giving on top of a budding social platform (facebook). Consumers donate $10 to charity:water on behalf of each friend they select from Facebook or Twitter. Each friend donated for is now added to the WaterForward book, and has the opportunity to “pay it forward” to other friends. Each person’s brief profile is displayed, showing how many people they donated to and what their total reach was in the chain (see screenshow below).

On a quick-ish sampling of 500 people who entered the book several weeks ago, I found that roughly 10% actually paid it forward, and to 3.6 people on average. Moreover, the overall reach of each person in the book was roughly 5.8.

So let’s consider our good friend Hampus (selected at random … thanks for being a good sport!). He has $70 that he wants to donate to the water cause, so he logs onto charity:water’s site and donates… his $70 creates $840 of economic value and brings 70 people-years of clean water to an African village. Which is great … but what if, instead, he had donated via WaterForward? Hampus, in fact, did, and donated $70 on behalf of 7 friends, and clearly has great friends as he eventually drove 74 people to donate $10 each (and it may still be growing!). That’s $740 in donations instead of $70, and it’s $8,880 of economic value instead of $840. WaterForward understands the pay-it-forward concept as a social psychology phenomenon that’s been true for millenia, and it’s pulling these levers on human behavior as an innovative marketing strategy for a good cause.

And more than just a smart marketing gimmick, WaterForward has the ability to drive the masses to give. In general, lower-income people tend to not donate to charity because they expect the rich to, but they feel more incentivized to give when they know other low-income people are giving (at least that’s what my professor’s latest research says …). By asking for only $10, underscoring the friends who are participating in the cause with you, and adding the vanity incentive of having your picture in a book (a la Million Dollar Homepage), WaterForward does well to address these psychological barriers to open charity to the masses. Like Kiva and Samasource, WaterForward is leveraging the power of the Internet to wean charitable giving off the heart-strings of the 1% and tapping those of the 99. This is starting to smell like sustainability.

That’s not all. I think we’d be short-changing WaterForward a bit if we stop in satisfaction at the economics and potential reach. At a higher level, I believe it’s an inspiring kick in the pants to the broader Tech community. I may be biased, but I believe the tech community to be more predisposed to innovative philanthropy than most for-profit industries. ”Changing the world” is in the DNA of the Silicon Valley, and the idea of having a massive impact on peoples’ lives (whether in microfinance lending or tricking them into playing silly games way too long) pervades tech entrepreneurs. Every once in a while, a Bill Gates will make billions then start a foundation. Or a Pierre Omidyar will IPO eBay then start Omidyar Network to invest in “socially good” businesses. And they’ll do good to inspire the next generation of well-meaning for-profit entrepreneurs to make it big, but in the meantime, perhaps techies have more to offer than money. If WaterForward succeeds, I believe it has the opportunity to be a shining role model to a powerful industry; it can really spur on other tech entrepreneurs to build innovative products for social enterprise.

Admittedly, my dotcom-crush on WaterForward may be a tad premature, as the uptake has been a bit underwhelming – after launching with expectations of millions of donors, they’re at only 21k a few months in. Perhaps that’s because of their decision to disallow people from joining the cause on their own volition (requires someone to invite you in), and there are certainly several product features they could add to make it a better experience (e.g., Klout score integration, gamification, general bug clean-up). But it’s a step in the right direction.

It’s my hope that this holiday season, you’ll take a minute to reflect before dropping $3 on that Starbucks latte to marginally lift your mood while you’re shopping for the $50 gag gifts, and consider how far skimming a bit off the gift-spend might go for someone in need.

Editor’s Note: This is the first article in an upcoming series “Student Voices,” highlighting HBS students’ observations and analyses on innovation in various industries and geographies. Josh Yang is the Chief Innovation Officer of the HBS Student Association and a 2nd year student at HBS. You can follow him on Twitter @joshhyang.