It was the end of a long journey, and at last they were alone. Their weary hearts had been forged in fires nobody else could ever feel or understand, and there was only one thing left for them to share. The silence was like a living creature, soft and silky, as they leant together, desperate not to misread each other’s eyes. Their mouths met, hungry yet unsure, and they stood frozen in the fiery release. At last, Frodo broke away and took the other’s hand. ‘Come to bed, Sam,’ he said.”

Blimey. Frodo and Sam? In bed together? Who could write such a thing? Well, thousands of people, actually. Stories of fictional men (or hobbits) getting down and dirty with each other — called “slash fiction”, after the slash that separates the names of the protagonists, as in Frodo/Sam, or the original pairing, Kirk/Spock — are one of the biggest crazes on the internet. Type “slash” into your search engine and you will find purple-prose tales of Legolas enjoying knee-trembling homoerotic clinches with Aragorn, Clark Kent getting jiggy with Lex Luthor, and Starsky engaged in a bit of sexual detective work with Hutch.

Slash is an offshoot of the internet craze for fan fiction, amateur stories based on characters from film and television. There are literally millions of them out there, and at least half end up with the male protagonists jumping into bed together.

When I blundered onto a slash website recently (a mistake any late-twentysomething fan of blond elves could have made), I naturally assumed they were written by some lunatic-fringe cult of gay nerds — not that I’m prejudiced, of course. So it came as a shock when my friend Callie, a scary American princess with flicky hair who can quote every line of ER and Dawson’s Creek, told me that almost all fan fiction, slash included, is written by bright young heterosexual women. Slash lets them write about relationships without having to deal with traditional sexual power struggles.

I stopped being shocked as soon as I had spent two seconds thinking about it. After all, everyone knows that men are obsessed with lesbians, and magazines from GQ to Playboy celebrate a man’s-eye view of the joys of sapphism — a world of lesbians who are eager to experiment with blokes. Women have traditionally kept their fantasies quieter, but why shouldn’t we have a little thing about man-on-man action?

Men, for all their good qualities, are visual creatures. The kinky “lesbians” they ogle are all pouting breasts and panting hair. Women want a different kind of fantasy. Female-targeted soft-porn magazines such as Sweet Action, which offers graphic shots of naked men in various states of arousal, fail to push the right buttons. What sells is a more internalised brand of eroticism, one explored by Catherine Millet’s The Sexual Life of Catherine M and the slew of bestselling erotic memoirs that have followed. I’m not saying that the thought of a naked, oily Legolas (for example) doesn’t make me want to pop out to the nearest elf shop, but what really gets women turned on is what is going on between the pointy ears.

This is one reason that slash has met with resistance in gay circles. Kirby Crow, a prolific slash writer, told me she is frequently accused of not understanding gay issues or what men get up to in bed. “Get over yourselves,” says Crow. “Gay men do not turn me on.” It’s not as if gay porn is hard to find. Heterosexual women enjoy slash primarily for “the intimacy between the male characters”.

Callie, who studied modern cultural intimidation at Harvard, matronisingly told me that men are frightened by slash because women use it to take control of men’s bodies for their own fun, just as men have been taking control of women’s bodies for centuries.

I made my main soul mate, Matt, read some slash. To start with, he was fascinated. “This is written by women?” he asked. “Kinky. I like it. Do you know any of them?” Then Matt got bored. I asked if he found it erotic and he looked at me as if I were crazy. “I mean, it’s funny,” he said, “but it’s rubbish, really — all these tortured, unspoken desires and strong men crying. It’s just Mills & Boon, with Batman and Robin instead of Lord Vulcan and Persephone. You don’t find it sexy, surely?”

Leaving aside how well Matt seems to know Mills & Boon, I do find it sexy, actually. A lot of it is rubbish, and a lot of it is more graphic than I am comfortable with, but a surprising amount is well written, well observed, funny and genuinely erotic. Matt doesn’t find it sexy for exactly the same reason that I am not turned on by airbrushed bimbos on the front of FHM: it isn’t aimed at him.

Now mainstream internet sites are getting in on the act. Lebby Eyres, the editor of Bint, an online magazine for professional women who get jokes about Jane Austen, but also want to know what’s happening on Big Brother, likes the “secret naughtiness” of reading stories online. She told me that Bint’s comic and lurid sex tales are an antidote to traditional male porn: “It’s not sexy for women to see pics of buffed-up models. Real sex is much sexier.” While men gaze passively at dirty pictures produced by a few mega-pornographers, women are busy creating a vibrant interactive culture that doesn’t depend on anyone being exploited.

I got so excited by all this that I wrote a story of my own. I’m not telling you how to find it (my mother is reading this), but suffice to say that I have always thought Chandler could do better than that annoying Monica, and Joey is obviously repressed. When I saw my story online, I felt a small but genuine thrill of liberation. Maybe Kirk/Spock really was the final frontier.

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