High Infidelity by Anna David (don't miss page 2). This is an article that was published a decade or so ago in Maxim Magazine, and is now available on the author's website.

Here are some choice excerpts:

Hillary, 27, who works for a nonprofit, claims to have cheated on every partner she's ever had. "My boyfriend thinks I'm this good girl. Most men just don't assume women are capable of what we're capable of." Not every girl's behavior is this extreme, of course. But it's time you found exactly what we're doing, why we're doing it, and what could be in it for you.

Why We Stray

Sometimes, we cheat for the same reason Brett Favre unretires every year: because we can. Says Rebecca, a 32-year-old New York-based editor who betrayed her man on a recent work trip to L.A.: "I never would have done it in New York, but everything feels sort of surreal when you're away from home -- like no one's going to know about it."

Unlike guys, many women also use infidelity as a form of revenge. Sara, a 31-year-old bartender, had a one-night fling because she didn't like the way her boyfriend reacted to her attempt to spice up their sex life. "I started taking pole dancing classes and got fully waxed, and he told me it was trashy," she recalls. "So I thought, Fuck him, I'm going to find someone who appreciates this. I invited over my ex. Two bottles of wine and one lap dance later, we were screwing on the couch. Frankly, it felt great. My ex made me feel sexy, not embarrassed."

In fact, if a girl feels really unhappy in a relationship, she may even start an affair as a way out. "My boyfriend kept pressuring me to marry him, and I didn't want to," says Carine, a 27-year-old law student. "The more we fought about it, the more I escalated a flirtation with a classmate. Finally, late one night, after a round of 'strip-studying,' we had sex on a deserted floor of the school library. When I told my boyfriend, he broke up with me on the spot. I felt guilty but also, truthfully, kind of relieved."

How We Pull It Off

So why haven't you been wise to women's cheating ways before now? For one thing, it's quite possible that we're uniquely suited to it. There are a few decidedly feminine qualities -- our intense attention to detail, the way we consider a given situation from every angle -- that make us pretty good at the game of deception. "Women are better at covering their tracks than men," says Ian Kerner, Ph.D., sex therapist and author of She Comes First. "They really think about what a suspicious guy would look for."

We also employ many of the same tactics that men have used on us for years, such as the time-honored "accuse you just as you accuse me" approach. When Chelsea, a 28-year-old boutique owner, went to a crowded bar with her boyfriend and "ended up running into" the guy she liked (translation: she knew he'd be there), she took off with her crush for an hour. "He lived upstairs, so we headed to his apartment, taking each other's clothes off in the stairwell on the way up," she says. "It was extra dirty knowing my boyfriend was just two floors away." When she returned to the bar and her boyfriend asked where she'd been, Chelsea turned the tables. "I said, 'I don't know what you're talking about. I've been looking for you everywhere. Where the hell have you been?"