I rarely have difficulty falling asleep because I habitually take a hit of Benadryl and a couple of Motrins about an hour before bedtime; zonks me right out ! Generally the only time I have trouble getting to sleep is (ironically) when I stay up too late and get lost in cyberspace…..
dennis' notes.... 
Cyberspace is the best way I know to lose track of time.
That is for sure…..