The Discriminating Letterbox

I am a discriminating Letterbox I welcome cards of a celebratory nature Congratulations, birthday & Christmas cards Personal, hand written letters (not customised round robins) Books of a size commensurate with my ingress Cheques and the year's first two calendars Postcards from family who still retain The ancient skill of writing I am a discriminating Letterbox I recognise the need to accept incoming bills Electoral queries, contracts requiring a signature All things bona fide, above board I am a discriminating Letterbox I do not welcome the paper deluge of spam Cascading through my mouth like a noxious flood I spit upon Holiday Brochures I defecate upon unsolicited insurance policies I incinerate funeral directors, will touts, credit offerings Catalogues, pizza ads, lottery scams And all associated spams and scams Polluters of the atmosphere Space invaders Carpet paper grenades Annihilators of rain forests everywhere As from tomorrow, I warn you, My lips are sealed