Ones I've actually heard, rather than heard of
I was waiting in a line of taxying aircraft at LHR when the Air France pilot announced,
“<long sigh>, Ladees and gentlemen, Air France apologise for zees delay, it appears that us being pushed back a few minutes late mean we naw ‘ave to wait for zee entire British Airways fleet to depart before we are allowed to go”.
His overly glum tone, and acceptance of the fact he was at BA’s hub made it amusing for all on board.
I was also on an internal flight in the US, when after a fairly "positive" landing, CC adopted part of the announcmeent to,
"please take care when opening the overhead lockers, as things will have sure moved after today's landing"!!!