As a kid I used to take the 36-hour QF 1 from Melbourne to London (70s/80s). Melbourne, Sydney, Singapore, Bombay (as it was at the time), Bahrain, Frankfurt, London. The only in flight entertainment was a few channels you heard through a pair of plastic tubes you stuck in your ears (no joke). Each channel was only an hour or so long so it got repetitive, but you did manage to read a lot of books. Oh yeah and of course there was smoking on the plane.

Currently it's a 24 hour flight with only a single stopover, in Bangkok.