America is swimming in a sea of Prozac, Zoloft, and Paxil! In 2006 alone, over 190 million prescriptions were given for antidepressants. The swim is a little expensive, though. On average, each pill costs between $2-3 for the patient. To add to the burden, the side effects of antidepressants can sometimes be negative.

Researchers at Britain's Essex University have found a much cheaper alternative with few side effects: nature. Seventy-one percent of those suffering from depression said a 30-minute walk outdoors "made them feel better about themselves." Of the 108 patients who took part in conservation projects, went cycling, or hiked, 94 percent said the activities brought about greater mental health. Researchers are calling the new treatment ecotherapy.