Ah, Ambien ... there is also that "Ambien effect" that, when not bringing forth legislators for 3 AM roll calls, does have some people up and functioning while still asleep.
I was actually going to mention the "Ambien effect." It makes sense to me that it might kick-start the brain. A lot of people legitimately have some really insane/weird side efects when they take Ambien. I wonder exactly what it triggers in the brain chemistry...