Casselman is a yoga-loving hiker and occasional winemaker who worries about animal rights and rain forest destruction. So it makes sense that he joined Care2 (care2.com), a 6.7-million-member site linking eco-activists around the globe. “I come from a small town where there’s no support system for people like me,” Casselman says. “Care2 makes me feel like I belong.”

But what does “belonging” mean? Are bonds forged on Care2 and other eco-networking sites really effecting change? Or are they only encouraging armchair slacktivism, the lazy man’s way to “make a difference” without breaking a sweat? Sign this petition to save the forests, dude. Don’t buy anything today and capitalism will tumble, making all the world’s ills, like, vanish.

In Internet years, Care2 is a wizened grandpa. Randy Paynter, a boyish, 40-year-old dad of two who spits out words as fast as an auctioneer, founded the site during the late-’90s dot-com boom as an environmental portal for green commerce. When it became clear that selling Seventh Generation–brand dish soap was a doomed business plan, Care2 evolved into a “one-stop shop for people who want to make a difference and influence society,” Paynter says. Care2 concentrates on connecting users to nonprofits and providing them with what he considers environmentalists’ greatest weapons: knowledge and opportunities to take action.

“If it wasn’t for Care2, many people—including myself—wouldn’t know about the issues that concern our animal-welfare and environmental movements,” says Care2 member Cindy Minde, 49, an endangered-wolf supporter in Apache Junction, Arizona. Care2’s mostly female members—homemaking moms, office workers, and young single gals alike - peruse reader-submitted and -ranked stories about endangered falcons, grab tips on veggie vittles, donate to nonprofits, discuss endangered Canadian forests and sign petitions to prevent Arctic oil drilling.

Oh, do they ever sign petitions.

With a click, members John Hancock petitions ranging from the serious (making Starbucks honor commitments to coffee farmers) to the silly (begging the Country Music Awards to rectify its oversight and give Rascal Flatts the Album of the Year award, which has zilch to do with the environment). These petitions may seem toothless, but Paynter points to direct results: Last September, the Bureau of Land Management nixed plans to drill near Alaska’s Teshekpuk Lake, perhaps swayed by Care2 members’ 20,000 petition signatures.

I, too, want to make a difference, so I enroll in Care2. I sign a petition or two, then head to the forums. In one called Race for the Rainforest, I learn about Indonesia’s rain forest fires. Every year, rampant fires create one billion pounds of carbon emissions—more than five times the amount that the Kyoto Protocol hopes to eliminate annually. When I’ve learned my fill, I enter Care2’s Daily Action area. Today’s computer-enabled difference-maker is downloading a picture of a smiling frog standing superimposed on an American flag and the words, “I Voted!” Change has never seemed so painless. That’s Care2’s intention. “We call it the ladder of engagement: Making it easy for people to make a difference is empowering,” Paynter says.

Translating Care2’s social responsibility to the real world, Paynter admits, is a tad trickier. Though he recounts stories of members marrying (six couples, at last count) and volunteering for nonprofits, Care2 has not yet sponsored marches, protests, or other large-scale activist actions. But Paynter says members have made changes in their own lives, ditching toxic household cleansers, increasing recycling, and using less energy. “Change happens at the level of individuals,” Paynter says, “and their ability to influence and connect with others.”

I came to Care2 with a healthy dose of skepticism. Call me quaint, but when I want to be heard, I click off my computer and hit the streets. In a shifting activist world, I still prefer agitating for change the old-fashioned way. But several weeks of membership allowed me to see that Care2 embodies some of the Internet’s best qualities. Fixing the world’s problems can be a cold, lonely, Sisyphean struggle, and while the site may not offer every eco-answer, I uncovered a wealth of news on underreported stories. And I found mostly welcoming forums full of folks eager to listen (save for those ubiquitous crotchety rabble-rousers). The sense of community was palpable, with members reaching out to provide real online kinship. “This is a movement that is important to people who sit at their computers and are unable to travel the world by other means,” Minde told me. “It lets us get involved and be heard.”

They say that everybody has to start somewhere, and for many people these days, an ever-growing virtual community of like-minded friends is somewhere that makes sense.