I can remember being one of 16 passengers (including about 6 kids) on a Qantas 747 trans-tasman in the 80's
We all moved (including the only first class passenger) into Business and had a whale of trip..................
IIRC there was a guy who was the only passenger on a very early Pan-Am 747 transatlantic flight in the early 70's - they were positioning it to Paris or somewhere from NY and stuck it down as a scheduled flight but didn't try & sell tickets - he was late for the standard 707 and so they stuck him on the jumbo