Sufferers of the baffling ailment known as chronic fatigue syndrome, take hope: For the first time, there's good evidence that the symptoms aren't just in your head, and experimental treatments may be coming soon. Over the past few decades, the syndrome has been a source of intense frustration both to patients diagnosed with it and doctors who try to treat it. The diffuse collection of symptoms can include incapacitating fatigue, muscle aches, headaches, problems with concentration. Doctors, meanwhile, have been mystified by the cause of the symptoms, and some have suggested that it's a psychiatric problem, leading to the coining of the dismissive label "yuppie flu." Now, researchers report