The O Wow! List: 15 Dreamers, Thinkers and Doers

The Extremist: Maya Gabeira

Who she is: One of the few female practitioners of tow surfing, a white-knuckle twist on the sport (involving jet skis and other equipment) that enables her to catch waves the size of office buildings.

Her breakthrough: Brazilian Gabeira, 24, holds the current record for biggest wave ever ridden by a woman: a 45-footer at a notoriously sharky break called Dungeons off the coast of South Africa.

Her biggest hurdle: Handling the psychological and physical aftermath of wipeouts so violent they're like underwater explosions. "I've been doing a lot of physiotherapy and trying to find my rhythm again," Gabeira says, of wrestling with a chronic back injury.

Lesson she's learned: Be less anxious and more strategic. In the past, Gabeira says, "I wanted to be everywhere at all times. Now I realize that I just have to be ready for the biggest swells, as healthy and strong as possible for when the conditions are right."

What's next: Spending time at Jaws, a fearsome, wind-whipped, highly technical wave a half-mile off Maui's north shore that occasionally tops 70 feet.

Breakthrough advice: Don't be afraid of fear. "When you're scared and uncomfortable, you can allow yourself not to do anything but sit there and feel that sensation. And you will go past it. The fear kind of mellows out, and what you're left with is more confidence." —Susan Casey