http://radar.zhaw.ch/resources/airtraffic.mov

Note the feed to east coast hubs in the early am and the lift to Europe in midafternoon hours. Also you can see asian traffic start up in the early hours as western traffic winds down at night.
Also note the guys on the lonely flights over the poles.

The poles are lonely, for sure, but the North Atlantic Tracks at night heading west with a 150 knot headwind is lonelier. Winter flying on the tracks always made me a little uneasy. Used to do Huntsville to Prestwick for fuel and then to Luxembourg and back to Windsor Locks. It was always nice to see the sun come up.