The First 500 Passenger Commercial Aircraft
In the 1970’s, Japan was experiencing fantastic economic growth and both ANA (All Nippon Airlines) and Japan Airlines needed more lift for their internal domestic routes. They approached Boeing and inquired about using the 747 for these high cycle, short duration flights. After investigating the possibilities, Boeing discovered that relatively minor changes (landing gear for instance), they could produce an aircraft that met their needs.
By eliminating 3 classes of service, galleys and other long range accomodations, the Boeing 747SR was born and able to carry as many as 525 passengers in this new domestic configuration. Later, those same aircraft were replaced with 747-400 Domestics capable of carrying over 560 passengers.
That was the first 500+ passenger commercial aircraft but now the new Airbus A380 may be capable of carrying as many as 800 passengers in a similar domestic configuration. There is some debate that such an airplane would be of use since the logistics of carrying an additional 300 passengers becomes almost unsolvable for existing airport configurations. No doubt Airbus would happily build the airplane if there is, indeed, a market for it.

I always wondered what ANA stood for!