Pandora
I used to have a laugh on my PA's but its not worth it now, because some pax are just waiting to get you into trouble
Might be worth remembering that you are not a nervous flyer.
A surprising number are and what may be hilarious to your colleagues, may scare some.
If a CC scares a passenger with a "funny PA", then the experience of that pax is bad and they may well compain (although I bet that a lot more suffer it in silence.)
As a frequent flyer, I'm not nervous, but I have heard most of these PAs many times and to be honest I'd rather have deliberate humour from a professional comedian, who has the skill to deliver it properly, although the odd moment of humour can be good, especially if it is spontaneous.
A couple of months ago, our airbus had just arrived on stand at London in the late evening and shutdown when there was a interuption to the power supply and the cabin lights all flicked off, but there was enough light through the windows to see clearly. Quick as a flash, one of the CC shouted out "has anyone got a quid for the meter?" Now I did find that very funny.