I know this a thread that has a view from Europe, but just think of the appeal from NYC! Non-stop from NYC to the City of London. Check in with a small crowd and easily be at the Bank of England 45 mins after landing at LCY. Magic!
And then leave Bank station one hour before the departure for NYC and be sure of getting the flight. Drink chamagne during the Tech Stop rather than queing in security at LHR - once you'v got there!
Goldmine.