I have mild narcolepsy, a lot of my symptoms are like CFS... although lately I've had insomnia due to depression, my ADHD medication, Vyvanse, helps me stay awake as well. That wasn't its purpose, but once I got on the right dose and have been on it for a long time, I stay awake quite a bit more than I used to, and it feels natural. I don't feel wired like on caffeine, I don't crave it when it's worn off -- and it does wear off and you can sleep. Waking up can still be hard for me, but once I drag myself from my bed, med takes about 30 minutes to work and it comes on gradually, feels like a nice, natural waking up.
I don't think it's very common, but I have heard of it being prescribed to treat sleep-related things.
So it's been a surprise help for me, I love it, but it's a medicine to be taken really seriously. At first my dose was too high and I experienced arrhythmia, excessive sweating, blood constriction in hands and feet, tremors and nausea. It's not something you can take whenever you want, just to be awake, so I'm not bringing it up as something you'd use like Monster or a cup of coffee. Maybe it's something any of you could talk to your doctor about, though, and if they're willing, perhaps start on a very low dose and acclimate and see if it helps? :]