Our next-door neighbours don't appear to have realised that their bathroom window is completely see-through even though it's frosted. They have their shower right next to the window and we get treated to full-frontal nakedness when we're out in the garden. H reckons we should tell them but I think that would be like telling them we've seen them naked and I think mortifying for us and them. Would you say something, and can you think of a tactful way of doing it?