Unfortunately (or rather I am lucky on this one), I can't fall asleep easily or anywhere a gate like area. I've secretly envied folks who can nap in airports when I couldn't do it even in lounges or most hotels. Insomnia could be a blessing, who knew!
But it does seem like a bad idea to let yourself go in ORD where agents would be only to happy to charge you than be sympathetic. If I ever snap out my insomnia, may it not happen in ORD.