Certainly nothing is unnatural that is not physically impossible — Richard Brinsley Sheridan, The Critic (1779).

Crowd Scenes. Different Strokes. Domination and Discipline. Flying Solo. Girls and Girls/Boys and Boys. Head and Tail. Pursuit and Capture. Serendipity.

These provocative themes from Letters to Penthouse are the stuff of sex fantasies. Within the book, hot-blooded writers speak in their unguarded correspondence of carnal rubbing and licking, devouring and pumping — in settings like a college dorm room and a backyard pool. The popular editions of Letters, with their cover-to-cover stories of daring experimentation, are evidence of an open-minded interest in the vast variety of imaginable sexcapades.

Try This at Home

Experimentation breeds excitement in the bedroom, sexperts say. Keeping things hot can be as simple as reading an erotic book or trying a new sexual position (maybe taking a page out of the Kama Sutra). Or consider these creative ways to make sure you and your partner don't become bored in bed.

  • Once in a while, pick a different place and time. Awaken your partner before the alarm goes off for some morning sex. Or try a 3 a.m. thriller for a change. Make love on the kitchen floor, consider visiting the guest bedroom for another change of venue, take your blindfolded partner to the nearest "no-tell motel," or drive a little farther to your own little love shack in the mountains. Stop on the way for a back-seat "quickie," or rendezvous with your lover at a private picnic spot.
  • Pick up some gizmos at a local (or not-in-your-neighborhood) sex store. Buy an X-rated video, leather accessory, vibrator or other sex toy. If the idea of visiting a sex shop has you squirming, look for some spicy gadgets on the Internet and in mail-order catalogs.
  • Take turns at role-playing. Rachel obliged sit-com "Friend" Ross by donning the Princess Leia look straight out of Star Wars. Some men might have a hankering for a classic French maid or a buxom blonde. Women might appreciate the chance to make a move on Elvis, or a doctor or a lifeguard — to each her own. Any fantasy is fine, sexologists (sex therapists) say, as long as it improves intercourse rather than detracts from it.

Women tend to have fantasies about relationships and great moments they've had, or "being-taken" fantasies, says sociologist Pepper Schwartz, Ph.D., while men often have "submission fantasies — she sees him, wants him."