After landing at EDI some years back, the cheery female CC was doing the chat about "thanks for choosing to fly ***, special rates available on car hire" etc when she suddenly gave a little scream and the PA stopped - which aroused everybody's interest...
Some seconds later she came back on, saying "sorry about that ladies and gentlemen, one of my colleagues just put an ice cube down the back of my blouse"
Cheered pretty much the whole cabin up no end!