The disorder in which one falls asleep very late and awakens very early. Even though the person may desire sleep he or she is simply unable to find that sweet sweet state of dream-land until the wee (thats right, I said "wee") hours of the morning.
Ive had insomnia for the past four years, I dont fall asleep until around 5:30 and I wake up at 7:15.
Jackass: Man I slept so good last night after the concert, I was asleep as soon as I got in bed.
Person with insomnia (me): I hate you more than life itself.