This is interesting...
Airbus A380 Faces Weight Problems
Just six months from the start of test flights, and less than a year before its first scheduled public flight, the Airbus A380 is still overweight by as much as 4 metric tons. The excess weight would hurt aircraft efficiency, resulting in financial penalties to Airbus. Engineers, however, are still working to shave weight off of the plane. About 25 percent of the A380 is made from composites, including carbon/epoxy and Glare, and fiberglass/aluminum laminate.
How about closing down the upper deck?