I was thinking of going around the world also. In July some new routes will be started up. I was thinking of hopping MDT-ATL-LAX-SYD-JNB-CPT-JNB-ATL-MDT.

Some polar routes would be SE Asia-JFK like Nick said.

Also, if you're cheap like me, eastbound flights are usually redeyes, and you've got one less hotel to fork up for. Plus you've got the tailwind.