I'm lost in the woods. It's nighttime. The light of a full moon shows me I'm surrounded by menacing-looking trees, curiously similar to the ones that pelted Dorothy with apples in The Wizard of Oz. Then I spot it, smack in the middle of the forest—a brightly lit office cubicle with a laptop inside. "That's funny," I say to myself. "You don't usually see office cubes in the woods." Suddenly it hits me: The cubicle is my dream sign, a signal to my subconscious that I'm actually asleep, that everything around me is a projection of my imagination. After weeks of practice, of studying ancient Tibetan dream techniques, of wearing a special sleep mask that flashed lights in my eyes in the middle of the night, of ingesting questionable subconsciousness-raising drugs purchased from untrustworthy sources over the Internet, I'm finally doing it. I'm having my first lucid dream.

This clarity hits me even within my dream state. I'm so thrilled by the revelation, I plop myself down in the cubicle and start typing. Yes, I wrote this story in my sleep.

This is merely one manifestation of the state of being known as lucid dreaming. You're asleep. You're dreaming. But you're aware it's a dream—unconscious but conscious (or is it vice versa?). On the one hand, this is a common enough phenomenon—one study concluded that as many as 70 percent of people experience lucid dreaming at least once in their lifetime. On the other, the ability to have lucid dreams on demand can be a difficult skill to acquire. A growing army of LD practitioners are training their sleeping brains to take maximum advantage of that lucid state, learning to control it in search of a mind-blowing natural trip. Imagine turning the inside of your head into the ultimate virtual-reality chamber, living out your deepest, most daring fantasies and desires, all without ever leaving your bed. Go ahead, fly to Zanzibar in your underwear. Play guitar like Jimi Hendrix—with Jimi Hendrix. Steer yourself not to a cubicle but to the corner office. Have sex with a supermodel. Or two supermodels. Literally anything you can imagine is possible in a lucid dream, because you have the keys to your subconscious.

Of course, the desire to control one's dreams is as old as dreaming itself, and unlocking the secret to lucid dreaming has long been a goal of philosophers, theologians, and scientists. Aristotle was said to have dabbled in it. Saint Augustine wrote about it. Eighth-century Buddhist monks devoted lifetimes to teaching a form of lucid dreaming known as dream yoga. Your hippie parents might have experimented with it at Esalen in the 1970s. But unlike many other New Age fads, lucid dreaming has a strong scientific foundation. And over the past 30 years, study after study has shown that lucid dreaming can have a profound impact on waking life. Researchers in Canada are using LD as a treatment for post-traumatic stress disorder. Sleep scientists in Germany are studying its applications for sports training—to improve both focus and performance in athletes. Closer to home, a doctor at a VA hospital in Los Angeles published a paper in January detailing the case of a patient with a 22-year history of chronic pain who cured himself overnight with a single lucid dream. "I'm no expert on lucid dreams," says Dr. Mauro Zappaterra. "But the man woke up with no pain. He said it was like his brain had shut down and rebooted. A few days later, he walks into the VA pharmacy and actually returns his medication—300 tabs of levorphanol. To me that's pretty convincing evidence."

Outside the scientific realm, lucid dreams serve as an idea lab for creative types: Actors and admen, inventors and game designers, fine artists, musicians, and filmmakers—like Michel Gondry and Guillermo del Toro—have practiced lucid dreaming. As the buzz about LD builds, it's gotten to the point where you can't stay up late drinking in the bar at the Chateau Marmont without overhearing a group of English indie musicians on their way home from Coachella going on and on about having lucid dreams in the desert or a starlet and a former professional athlete nearby gushing that LD is "better than TM."

There are now scores of lucid-dreaming websites offering online courses and dozens of LD-training apps on iTunes (one of which was downloaded more than 500,000 times in its first six weeks) promising to prepare your mind for dream flight. There are weeklong workshops in Hawaii, seminars in the Hamptons, and—the obligatory indicator of an incubating trend—TEDxTalks. And why not? Who wouldn't want to be "the producer, writer, director, and star of your dreams," as the promotional copy for one lucid-dreaming meet-up in New York City promised.

"Yeah, it is becoming trendy," acknowledges Charlie Morley, a 30-year-old British lucid-dream teacher and the author of Dreams of Awakening: Lucid Dreams and Mindfulness of Dream & Sleep (previously he was a rapper in a Buddhist hip-hop group). "But it's not just hipsters doing it. It's all sorts of people, because there's no equipment to buy, no club to join, no money you have to spend. Anybody can do it."

However, not everyone has the same aptitude for lucid dreaming. There are those who pick it up instantly—Morley taught himself at 16, with no training—zooming to the moon on their first trip, while lucidity-challenged dreamers plod along for months before achieving liftoff. The reasons elude scientists, though a recent—and perhaps unsurprising—study at MacEwan University in Canada discovered that gamers are more likely to experience lucid dreams than non-gamers ("Virtual reality is virtual reality," explains one of the researchers). Also, those who tend to remember their dreams seem to have an easier time mastering LD than those who wake with no memory of them. But another recent study, this one at Goethe University in Germany, holds out hope for even the hardest cases: Sleep researchers there found that a mild electric current delivered to the frontal lobe for 30 seconds during rem sleep triggered lucidity 77 percent of the time. Can it be long before wearable LD brain shockers start appearing alongside Google Glass and Oculus Rift?

The more people experiment with lucid dreaming, the more distinct manifestations of it we will find, yet there is a certain universality, too—almost all lucid dreamers have the impulse to do the same thing. They fly. "Oh, man, being able to fly," Morley says, smiling broadly at the memory. "Flying is amazing. The feeling of floating above the earth, free from gravity—it's so liberating. I used to go to bed early on Saturday nights just so I could fly in my dreams. I got stuck doing that for two years. All I did was fly around and go to orgies."

You'd think it would be addictive, but sooner or later boredom sets in. "After you've flown for the thousandth time, you start looking for other, less superficial applications," says Tim Post, the 30-year-old founder of the LD website Snoozon.com, who taught himself to lucid-dream after being inspired by The Matrix. "You start trying to bridge your lucid-dream experience with your waking life. You start asking, 'How can I learn from this? How can I use it to be a better person, or get ahead at work, or rehearse for a sporting event?' Eventually, you look for practical applications."

You don't have to look far. Like that case of the VA patient who cured his pain with a single lucid dream (involving beautiful musical tones and strands of giant DNA made out of cookie dough—hey, whatever works). It can be useful for coping with nightmares, overcoming shyness, or dealing with bereavement, and it can be helpful for practicing for a big presentation, pumping up one's confidence, or solving creative problems (Paul McCartney famously puzzled out the troublesome melody of "Yesterday" in a lucid dream). In many ways, LD is the perfect self-help trend for our super-busy, technology-obsessed times. Not only is it just the right mix of ancient Eastern philosophy and cutting-edge brain science, but it also lets you get twice as much done in a day by turning your sleep hours into a night shift.