I was thinking if there were any airlines out there that you can circle the entire earth on, using ONLY that airline, no codeshares. It doesn't have to be all one flight. The closest I could come was with SQ. You could go from SIN to the US west coast, and from the US east coast back to SIN via Europe, but there is that gap from the US west coast to the US east coast. I know that UA had their round-the-world flight, but not anymore. You can also get pretty close on NW going from the US to India via Europe, and you could go from SE Asia to the US, but there is again a gap (India to SE Asia). Can you think of any carrier that you can circle the entire earth on?