Today I enforced the Language skill levels in BRP rulesystem.
So I explain to one of the characters what sort of speech their character is allowed so later during the game after the characters are deep in conversation. Alexandra asks Bran the bounty hunter if he wouldn't mind collecting the bounty on a criminials head...

This is how it went
Alexandra (Female Player) 'Bran, Do you do head?'

Players and GM burst out laughing

Bran (Male Player) 'I'm not that sort of barbarian.'

Alex 'But its bleeding all over.'

Was the end of a sensible game