Boeing has had a number of aircraft in its Eco-Demonstrator program.  The most recent one is a 787-10 that they have been using to test air traffic control innovations including some trans-Pacific flights in coordination with control agencies in various Asian countries.  When I shot the 777 demonstrator a while back, I thought it was the end of the line for that plane and it was heading to desert.  Apparently not.  It is back and flying and made a trip to the Paris Air Show.  I got it on its return recently from Europe.  Maybe we shall see more of it in the coming months.  Now to try and find the 787!