An extraordinary house exists on Fifth Avenue in New York. The architectural designer Eric Clough embedded 18 clues in the apartment of the Klinsky- Sherry family, leading them on a scavenger hunt through the rooms of their home. A book with a narrative about a mystery, hidden behind paneling in the front hall, offered clues to a search that included ciphers, riddles, poems and custom-built furniture with hidden drawers and panels. Rather like living in a Griffin and Sabine novel, actually. To find out how the story unfolds, read more about the puzzle house here. For more visual clues, see the slide show here.
This could be a fun idea on a smaller scale, too — what about a secret door or panel in, say, the kitchen, where a secret message can be left for your partner to discover while brewing the early morning coffee?