Around the world you can find plenty of parked Boeing 787s at the moment.  Problems with the Rolls Royce Trent engines for this type mean that airlines have been pulling engines from various airframes in order to keep others flying.  ANA uses Rolls engines on their fleet and I saw this aircraft being pulled around a taxiway at Haneda.  Both engines were off making it look quite odd.  It will certainly be a lot lighter than before but, somehow, I think that isn’t going to make it more efficient!