To many, sleep is something that just comes and goes, a part of life so ingrained and natural it just fades into the background, never noticed, never missed. For those who can't find it, however, it's something almost like a wound, an absence of something inside of you, a hole that gnaws until the discomfort fades into the back of your mind. Whichever extreme you swing to, the point is that sleep, or lack of it, still remains behind our eyes, deep in the mind, always present but never closely examined.