Since their inception, hugely popular social networking websites like Friendster, MySpace and Flickr have been subtly making over the relationships between grassroots progressive organizations and their members.

It's an uneasy affiliation for political groups, nonprofit organizations and independent magazines that are intrinsically anti-corporate, whether by ethos or by size, especially since conservative powerhouse Rupert Murdoch's News Corp. bought MySpace for $580 million in July.

Still, the sites are ostensibly democratic: Everyone who joins them can have their say. And it makes sense that groups with limited resources would be drawn to them: The sites are free to join, and it takes just a few clicks to post a profile.

A recap for those who aren't sure how it works: Anyone who has a profile can invite other users -- or, in this case, organizations -- to become a "friend." If the organization accepts, its picture will appear on the user's homepage, linking the two profiles to one another. MySpace allows users to create their own web pages with pictures, blog templates, and audio and video streaming capabilities, making the site particularly popular with musicians and bands.

Both MySpace and Friendster allow users to join groups that organizations can use as online discussion boards. They also have bulletin boards, so an organization can send out notices about upcoming events that will immediately appear on the bulletin boards of all that organization's friends.

The sites' public nature makes it easy for grassroots groups to do what they have always needed to do: build community, especially among a younger, notoriously hard-to-reach demographic. Clearly, that demo is already there: Friendster says its users are between 16 and 35. And, though popular opinion claims MySpace skews younger and hipper, the site says its users are between 18 and 34. The former "gave us great access to young folks in particular, folks who are self-selected, the kind who would be interested in what we were offering," notes Sharif Corinaldi, the coordinator of progressive nonprofit Swing the State.

The group facilitated grassroots political activism (it sponsored voter drives to red states across America) between friends during 2004's presidential election, so it made sense, Corinaldi says, to have a presence on a social networking site, where people "speak in terms of being friends." Friends who, when banded together, exert political power. The sites are becoming the equivalent of an old boys' club for the cyber-savvy generation (with girls allowed). Corinaldi notes that many progressive causes, which worked in coalition during the 2004 campaign, were all linked on Friendster, including "Dyke March, Department of Peace, IndieVoter.org -- all of the lefty groups."

Some organizations have used the sites to forge more intimate relationships with their members. Both Friendster and MySpace have "absolutely been an excellent way for us to meet and connect with Venus readers," says Amy Schroeder, editor-in-chief of the independent feminist-inflected culture magazine, which has had profiles on both for about two years. Schroeder, who is based in Chicago, uses the sites to find out more about her 60,000 mostly twenty-something readers' preferences, from bands to books and beyond, helping her decide what kind of content she wants in the magazine.

She has also used the sites to post calls for submissions -- most recently, to find young, female Hurricane Katrina survivors to write about their experiences. And, Schroeder says, her "friends" pass along great ideas: "Instead of us just listening to publicists or depending on reporters and writers for legwork to find fresh stories, we depend on readers."

In the cutthroat magazine industry, everyone is competing for the same audience -- many of whom seem to have abandoned print entirely. It's become imperative for magazines, particularly not-for-profit and independent ones, to reach readers in other ways, and social networking sites give them yet another venue to connect with their favorite publication. They also allow the magazine to triangulate, connecting readers to each another.

Schroeder says fans of the magazine often approach her at events and say how grateful they are that they met other Venus readers via the social networking sites and have since teamed up to do a project together. Many make use of the bulletin board postings. They'll say, "I'm starting a band and I'm looking for a bassist," says Schroeder. "We see a lot of that kind of networking." In that way, the sites serve as a clearinghouse for the like-minded, like a targeted Craigslist.

And though the effects of community building via these sites are hard to quantify, some groups want to try. Hands On Bay Area, a nonprofit organization that matches volunteers to a multitude of projects, is one. Every year, the group organizes a day of service; last year was the first with projects not just in San Francisco, but all around the Bay Area, and about 1700 volunteers were needed. "The challenge is getting 1,700 people to do that," says Sandeep Chivukula, who works with the group.

Hands On partnered with Friendster last year, in the hopes of attracting enough volunteers for their October 15 event. In return for sponsoring the day, Friendster offered to help with publicity, showcasing the event in its news alerts, which are visible to any Bay Area members who log on to the site.

According to Chivukula, about 60,000 people saw the alerts. "Even if only 1 percent turned out to volunteer, that would be 600 people," she says. Unfortunately, though, the event was a success. "We weren't set up to track where the volunteers were coming from," she adds. "It's hard to tell what the conversion rate was, from clicks on Friendster to volunteers"

Still, it's these sites' ability to target their members geographically that makes them so appealing. MoveOn.org, the phenomenally successful progressive organization, has been using the Flickr site to post pictures of their members at vigils and other political events. "We know, because of our members, where specific photos were taken, [down to] a zip code. Sometimes down to a street address," says Patrick Michael Kane, the group's CTO.

"One thing I'd like to play around with in the future is geotagging," Kane continues. (Geotagging is embedding geographical information about the photo into the photo's data, so a user would easily know where it was taken.) "The way Flickr works, you can show people, 'OK, not only here are people becoming politically active, but here are people becoming politically active in your neighborhood and at your city hall.'"

Which is useful not just for inspiring MoveOn.org members, but for piquing the interest of other Flickr members as well. "I certainly think there's a perception that MoveOn.org members are traditional activist types," he says. He hopes that one look through its Flickr pictures will prove that the group's membership isn't exclusive to hippie-dippy placard-wavers. "When you look through these photos, it's clear that it's your mom, it's your aunt, it's the 30-year-old next door with three kids," says Kane. "For the general public, it lets them see that regardless of their political stripe, here are real people becoming politically engaged."

There are drawbacks, of course. The thing with social networking sites is that most users are there to be social and make "friends," which can deduct valuable time from work agendas. Indeed, it takes time to respond to friend requests and maintain the site, claims Debbie Rasmussen, associate publisher of Bitch, an independent feminist culture magazine with a circulation of 47,000. Plus, she doesn't want to divert attention from the Bitch website which, like Venus' site, has original content. But she "can see how it's effective for smaller organizations that don't have the resources for their own websites."

For political groups, the time devoted to maintaining presences on these sites is even more questionable. The MySpace Democrats group began in the fall of 2004, and since the presidential election, the group's message boards have become a central clearinghouse for liberal activism. Its political bent has made it "a target of trolls and other disruptive activities," says Omar Yacoubi, the group's former moderator. It's also up for grabs as to just how much good the site did for the Democrats' cause. "I kept track of donations made to the Democratic party while I had a tracking link up, [and] none were received," he says.

Yacoubi's observation gets to the heart of the problem for political organizations: Do social networking sites actually incite action? "I think a lot of people out there, even some people who are not Move On members, would be happy to be a friend to Move On, but would never show up at a rally, would never give a dollar, may not even want to receive an email from us," says Kane. Instead, he worries, people would befriend the group simply as "a badge of 'These are my political beliefs.'"

As for the other people he would imagine wanting to be MoveOn.org's "friends:" "I think those people are already on our list. We have a good way of communicating with them already."

Besides, Kane asks, "How do you use MySpace when you're doing a campaign [targeting] Fox?" All of the sites have fairly draconian terms of service, he claims: "You're here because we say you can be here, and if we decide you shouldn't be here, you're gone tomorrow. From a political standpoint, that gives you pause."

In fact, this issue was highlighted in December, when some users noted that any references to YouTube, a video-sharing site and MySpace competitor, had been erased or blocked from appearing on the site. Irate users complained about corporate meddling, and MySpace, which claims the disappearance was a misunderstanding, soon rectified the situation. Still, some users cried censorship. Bitch even had to receive special permission from the powers-that-be to use the magazine's title on Friendster, since it was considered an obscenity. "We're anti-corporate in our mission, and this puts us in a weird position. Do the ends justify the means?" ask Bitch's Rassmusen.

For many magazines and nonprofits, they do. "We have so many obstacles to getting the word out about the magazine, and fighting conventional magazines and glossies, that we have to do what we do and use existing networks," she says.

But as Kane points out, "Do we want Fox to know who Move On members are?" The sites are proprietary and, in the same way that groups can use the sites to find out more about their members, well, so can the sites themselves.

Do liberal groups really want to provide market research for the enemy? For now, at least, many groups are taking their chances.

Like most children of the '80s, I had received a reasonable sex education via pop culture by the age of 11. In fourth grade, I asked my mother what Darryl Hall was referring to when he sang "I Want to Play that Game Tonight," and laughed knowingly when she answered "Monopoly." I suffered eye strain from repeated late-night viewings of the Spice Channel and was a longtime aficionado of The Joy of Sex. Still, nothing quite prepared me for the copy of Our Bodies, Ourselves (OBOS) I found in my parents' basement.

It wasn't the detailed diagrams of the female reproductive system, or the drawings of six different types of hymens that captivated me. Nor was it the righteous, womyn-power assertions such as, "We are learning to live our sexuality on our own terms." No, it was the book's explicit, unflinching description of fantasies: real women revealing their most private erotic imaginings about horses (ew) other women (less ew) and men (totally awesome, as I may actually have said in 1986). I read the scenarios over and over in the privacy of my locked bedroom, until I finally left for college, where the logistics of living with a roommate promptly put an end to that.

The eighth edition of Our Bodies, Ourselves arrives in bookstores this month. Touted as one of the most lasting contributions of the second-wave women's movement, it has been called the definitive women's-health reference of the last 35 years. But ask the daughters of its original intended audience � the women who now call themselves the third wave � why they love it, and they'll confirm it wasn't the advice on healthy eating or bicep-building that mesmerized them in their youth.

"I definitely remember reading the sex parts, especially the lesbian parts, and being like, this is amazing, they're real people talking about sex," says Liza Featherstone, the author of Selling Women Short: The Landmark Battle for Workers' Rights at Wal-Mart. "It must be like a teenage guy discovering Penthouse Forum. Except better, because these aren't stories about people having sex in airplanes that are probably made up. It must be the way that people experience amateur porn now."

It's true: reading OBOS isn't entirely unlike watching a jiggly, implant-free woman and her paunchy, real-life boyfriend wrestling naked in front of their home cam. The fantasies in OBOS weren't airbrushed, and neither were the people. And though one friend of mine claims that a childhood viewing of "the crazy picture of two fat lesbians, one of them in a wheelchair" led her to temporarily resolve that sex was absolutely, unequivocally grody to the max, most of us felt deeply, intuitively comforted by the knowledge that we could think our dirty thoughts and look like our less-than-centerfold-worthy selves and still get some action (eventually).    

Hell, you wouldn't even need a lover. (That's the book's very "Saturday Night Live"-sounding term, not mine.) In fact, OBOS picks up where Gloria Steinem's "A woman needs a man like a fish needs a bicycle" maxim leaves off. Every edition devoted an entire section to sisters doing it for themselves, sexually speaking. From the story about the gym teacher who feels up her female students to the girl who imagines sleeping with her brother because he's "19 and groovy and looks just like me," OBOS provided plenty of things to think about while doing the deed. "I don't remember a lot about the rest of the book," says Marisa Meltzer, a freelance writer who was given OBOS by her mother one Christmas. "I was like, let's get back to the masturbation scenes."    

I'm pretty sure that when the book was first published in 1970, its feminist authors weren't attempting to recruit young ladies to their cause with a bait-and-switch -- get 'em with the sex stuff, then pump 'em full of women's lib. But it worked anyway.

"The book definitely politicized me," says Christine Cupaiuolo, online editor of Ms. magazine. "It made me more aware of the issues. It showed me a paradigm existed that I could work and live in." OBOS illustrated that women could (and should) march in defense of abortion rights, fight the inadequacy of the American health care system, and tell their husbands to shove it when they skipped the foreplay -- but still have a threesome or fantasize about being spanked. In the OBOS worldview, political action was an easy bedfellow of un-PC sex.    

And by inadvertently appealing to pre-pubescent girls' hormones, it provided a much-needed corrective. "One of feminism's jobs has always seemed to be about giving women sexual agency and acknowledging they're sexual people, and yet that's not feminism's identity," says Jennifer Baumgardner, the author of Grassroots: A Field Guide for Feminist Activism. (The North Dakota native confesses to a penchant for a certain OBOS scenario involving a bathtub and warm running water. "It was cold in Fargo," she explains.) As far as OBOS readers knew, feminists weren't man-haters -- they seemed to love not just men, but also women, bondage, polyamory and water sports.    

And all this free-to-be sexuality wasn't just appealing to girls. "I was first exposed to naked women in Our Bodies, Ourselves, well before Playboy," says Mike Carnegie, a 30-year-old graduate student and artist in L.A. "So any titillation would have always been wrapped up in some kind of awareness of feminist body-image concerns." OBOS may have stealthily made a generation of men more feminist, though Carnegie isn't convinced his experience with OBOS was entirely positive. "On the dark side, it contributed to a kind of imperial guilt in my teens � like jerking off to natives in National Geographic." But he admits that when the time came, "I probably knew my way around a vagina better than I might've otherwise. Or so I like to think."    

To me, OBOS has exhausted its usefulness as a pornographic accessory. The scenarios don't give me the same spark they did, back when I wasn't just like a virgin. But the newest edition sits in an exalted position on my bookshelf, and not just because I'm nostalgic. Now, OBOS is what everyone says it's supposed to be: a kind, tender, essential how-to manual. The new edition covers all of the old sexual stuff, plus more recent health-care issues � there are sections on plastic surgery, antidepressants and menstrual suppression, not to mention a misguided anti-Brazilian-bikini-wax diatribe � but the fierce feminist analysis, nowhere to be found in the average reference book, remains.    

It's a good thing, because our sex lives may be even more embattled now. With TV gays making network execs rich while real-life queers can't even get a tax break, OBOS's loving -- and lusty -- depiction of lesbian sex, coupled with its explorations of institutionalized homophobia, remains nothing less than radical. And as abstinence-only advocates tout the value of technical virginity -- and their young charges comply by substituting unprotected oral or anal sex for vaginal intercourse -- OBOS continues to provide comprehensive sex education without a hint of compromise.