chronic fatigue syndrome
"Modafinil has been a miracle for me. I suffered with chronic fatigue syndrome for 20 or so years, usually accompanied by severe depression. My  doctor called one day and said his two other Chronic Fatigue Syndrome patients has had remarkable success with this medicine and he wanted me to try it. Prior to trying it, my depression had lifted, but the fatigue always remained. Within a very short time, the fatigue lifted and NEVER returned. I experienced not a single side effect, and I have developed no tolerance problems with it. As a result, I have been using it successfully now for 13 years! My depression comes and goes, and most medications have proved useless over time, but the fatigue.... it's gone!"