New York Times Bending, Posing and Teaching Beyond the Mat is a nice article about karma yoga, taking the practice to the prisons, shelters and schools as a selfless act of service.

Research in the United States on yoga's effectiveness in helping treat drug addiction or mental illness is limited. Most studies have been done on a small scale in India, and the findings aren't universally accepted... But yoga's function as a stress reliever is not in dispute. “Yoga and meditation do several things, and perhaps one of the most important is that they allow individuals to cope with stress better," said Sat Bir Khalsa, an assistant professor of medicine at Harvard Medical School who studies the medical effects of yoga. "At the core of a lot of addiction is a search for that kind of relief from the stressful world."

There have been two recent articles in the Washington Post that I have not mentioned before: "The Family That Ohms Together..." (January 4, 2008) and Om for the 'Olidays: Breathe. Release. Repeat. What Stress? (November 20, 2007). Both mention Thrive Yoga. Also seen the feature on Diamond Dallas Page, a three-time World Wrestling Champion who has taken the virtues of yoga to the troops in Iraq and Afghanistan. He has a Yoga for Regular Guys DVD and a book out. See his site.