Let's see here. Right now it's nearly 5AM, an appropriate time to find an "Insomnia Club", lol.
I've had this issue for years now. I blame it mainly on technology, it's completely fucked up my biological clock. Staying up all night playing video games, for example. One thing that I leanred, the kiss of death for insomniac-prone people would have to be MMO's, for sure. Console gaming, i'm able to keep relatively under control. When it comes to addictive long-term games, though, wooooo. I once went almost 3 days without sleep, due to piling on school, a MMO, and a "social life" all at the same time. So fucking unhealthy.
Typical time I go to sleep is 4AM, it's relatively.. reasonable. 2AM would be ideal. I'd like to eventually get myself back into tip-top shape, instead of feeling like a zombie through out the day, then get sudden surges of energy at night.
When I wake up, it really depends. Sometimes i'll pull an all-nighter, sometimes i'll get a couple hours of sleep, and sometimes i'll get a full 6 hours in there. I don't have a recurring time dependent daily schedule. I do try and get my morning yoga and jogging in there, though. It keeps me more level headed, without it I go a tad crazy.
So, rah rah rah to you insomniacs! ;D The night life is so exciting, isn't it?