I have "slept" at JFK one night about 5 years ago. FLight on AF from CDG was late leaving, rerouted to Montreal for more fuel due to thunderstorms, got stuck in Montreal and finally made it to JFK 12 hours after we were planned to get in. No hotel comps avaliable, no outgoing flights to the west coast at that time of night so we camped in a boarding area. Sucked big time. We got a really clean bathroom in the morning since we waited until the lady finished. No food in the concourse either. Burger King ran out of meat.