A man walks into a bar and orders a pint. After a few minutes, he hears a voice that says 'Nice shoes'. He looks around but the whole bar is empty apart from the barman at the other end of the bar. A few minutes later, he hears the voice again, this time it says 'I like your shirt', again there is no-one around. He beckons the barman over and tells him whats been going on, to which the barman says 'Ah, that would be the nuts sir, they're complimentary!'