Today, billboards across the UK carry a brand new four-word message in capital letters: I LOVE YOU EARTH. People more used to driving past slogans for Carphone Warehouse or Kwik Fit Tyres may wonder what it is all about. Is EARTH the brand name of a new online bank, perhaps, or a furniture superstore? Similar slogans, such as I LOVE YOU WALKERS CRISPS or I LOVE YOU GIRLS ALOUD, would ...