Sleepy dude

I don't know what it is, but I've turned into one sleepy dude. After I get home from work and have supper I sit down at my computer and have a tendency to flat-out fall asleep. Sometimes it's just for a couple of minutes, and sometimes I just catch my head falling down. And sometimes it's for extended periods... sitting upright in the chair with my head hanging there like a slack bobble-head. slobber dripping from the lower side of my slackjaw.

The odd sleepiness started 2-3 months ago when I got all out of sync and started taking naps after getting home from work - I think messing up my sleep cycle considerably. So far the best solution seems to be stand up while I'm doing stuff. I can't get my system to reset back to normal state at the moment though.