LHR-HKG on Friday night, HKG-LHR on Sunday night has become a bit of a routine over the last couple of years. Makes the two-night stops seem like a bit of a luxury. And to think that this is nothing to do with work, but is all supposedly leisure travel ...
Best trips that I heard about were those by the guy who had to do LHR-JFK on the early Concorde on Monday mornings, meet East Coast colleagues in the lounge until lunchtime, and then return to LHR on the late Concorde. Did this every week for a year, apparently.