We were in Dublin a few years ago on a hen do and saw Ronan Keating come out of a posh hotel across the street. We were half cut (drunk) of course so we all 10 of us stood there swaying and started singing
LOUDLY,
"You shay it besht, when you shay nothing at all !"
and he paused at his limo door, glared over at us and yelled
"SHUT YER GOBS YA BUNCH OF CULCHIE CUNTS !"
We literally fell on the pavement in hysterics. It was very messy and some wee was involved.
Best insult ever ! It's our go-to insult now to diffuse tense girlie confrontations.
PS , culchie is a country bumpkin.