I used to do the Continental flight from Newark NJ <----> Hong Kong. or Tokyo 16 hours EWR--->HKG taking the polar route. Tokyo was slightly less polar, but the cool thing about Tokyo -->EWR is that you would be scheduled to arrive 20 minutes before you departed Japan (by crossing the Intl. Date Line). All of these travels were in B777-200ERs with GE 90 94B engines. Man can they put out some power! And very quiet once they spool up to full idle. Of course, "ignition to idle" is very much within the resonance range of the aircraft, but....