I know my father-in-law used to travel frequently on United or Northwest from PIT to Kuala Lumpur. He sometimes circumnavigated, usually going west (I can't think of once where he went east). If I remember correctly, it was something like this:

Pittsburgh - O'Hare - San Francisco - Tokyo or somewhere in Japan - Kuala Lumpur - London - either JFK or Dulles - Pittsburgh

I'm not sure of the mileage, but it's all northern hemisphere, and I would think that you would have to dip down below the equator to get the "Earth's waistline" mileage.

Good luck and let us know how it goes.

BTW - He did this every-other-week for 6 years, and was either in Phoenix or Boston on the other week. His United miles were through the roof. I believe he said he got a letter from them saying he was in their top 25 all time accruers.