In his aerie atop a mortgage broker and a massage therapy center on California Avenue in Palo Alto, Calif., Jim Fruchterman seems like the prototypical Silicon Valley electrical ­engineer–entrepreneur. He’s in his late 40s, with close-cropped brown hair, a white cotton dress shirt, and khaki chinos. He’s nursing a sprained thumb from too much foosball.

His office has the obligatory whiteboard littered with lists and block diagrams; there’s the warren of comfy-chaotic cubicles outside his door and the gentle clicking of his engineers pecking away at their high-end PCs.

Fruchterman could be any of the Valley’s countless billionaire wannabes. But he isn’t.

One of the mainstay products of his six-year-old organization, The Benetech Initiative, is Martus, a software tool for collecting and disseminating data on human rights abuses around the world. Benetech also created an online repository of books for people whose disabilities mean they can’t read printed text. Up next: low-cost land-mine detectors for use by humanitarian organizations around the world. Needless to say, Benetech is a nonprofit.

Can one clever and determined techie make the world a better place? Bill Gates, to cite the most obvious example, is sure giving it his best shot. His efforts, through the Bill & Melinda Gates Foundation, to rid the world of malaria and other scourges, bolstered by US $26 billion of his own money and a pledge of stock worth $31 billion from his friend Warren Buffett, made headlines worldwide in June. But Gates and Buffett are doing philanthropy the old-fashioned way, following a script written more than a century ago by Andrew Carnegie, J. Pierpont Morgan, John D. Rockefeller, Cornelius Vanderbilt, and others. They started companies that made them hugely wealthy--and then spread the wealth later in their lives.

For the past 20 years, by contrast, Fruchterman has been working on a totally different proposition: what if the company itself, and in particular its engineering talent, can be harnessed directly to the cause of social good?When he first started pursuing the idea, it was pretty far out. Now, it’s common enough to have a name: social entrepreneurship. Although Fruchterman’s Benetech is the clearest example of the movement, there are others in the Bay Area: Project Impact, based in Berkeley, Calif., is producing low-cost hearing aids and developing intraocular lenses for use by the hearing- and vision-impaired in developing countries. San Francisco’s KickStart International develops irrigation, building, and sanitation technologies and uses them to encourage entrepreneurial efforts in Africa.

”Back when Silicon Valley was getting started,” recalls Chris Eyre, managing director of the Palo Alto venture capital firm Legacy Venture, ”it was all about an engineer leaving a company and starting something and becoming successful, and then other guys thinking that if he did it, maybe we can. Maybe we’re seeing the seeds of that kind of entrepreneurial revolution right now in the social sector. Maybe 30 years from now, we’ll look back and see Benetech as the pioneer in the way Fairchild Semiconductor was, with many companies and people that came out of it and started other things.”

”He’s a Johnny Appleseed,” says Jed Emerson, senior fellow with the Generation Foundation, a London-based investment firm and a visiting fellow at Oxford University. ”He’s bringing people into Benetech that want to work in their nonprofit environment, and over time those folks will spin out and start their own companies.”

And his efforts are not going unnoticed: this past September, Fruchterman received a MacArthur Fellowship (known as the ”genius grant”).

Fruchterman himself, who says he didn’t grow up with a passion to change the world, sees his work as a natural outgrowth of the engineering ethos. ”We techies love to solve problems,” he says. ”We love to figure things out and love to have recognition for it.”