Kino MacGregor is the youngest woman ever to be certified to teach Ashtanga Yoga by its founder Sri K. Pattabhi Jois in Mysore, India. She has completed the challenging Third Series and is now learning the Fourth Series. (There are just a handful of people in the world who have accomplished this) She is quite an inspiration, not only for her awesome strength and flexibility but also for her playful, uplifting spirituality and work as a life coach.
Check out her doing some awesome advanced poses.
Then, if you want more, a sample of her teaching style