Well when testing new planes Boeing and Airbus have to do long stress tests, so they just plotted a route around the US. However, since it doesn't matter where they go they spelt out 787 and the Boeing logo.
Oh that is brilliant, hahahaha!
I have an iPad app called PFHD (Plane Finder HD) which puts a little plane on top of the Google maps. This kind of stuff is such fun to watch!