E' Ya Fanny
A loud Scottish way to tell someone they're an idiot or they did something so stupid it made the moon laugh. It's also used when someone talks so badly it sounds like a broken kazoo.
'E' ya fanny!' my brother screamed when I tried to tell a joke and it came out as a whisper.
'E' ya fanny!' my neighbor yelled when I tried to mow the lawn and just sat there.
'E' ya fanny!' my dog said when I tried to teach him to dance.