Don’t have cash for rooftop solar panels but still want a green roof? Dutch designer Klaas Kuiken has a solution: rooftop tile birdhouses. Kuiken explains, “Nowadays birds are not welcome under roof tiles anymore, so they lost a beautiful nest place. Placing a house on top of a roof tile [creates] a nice place for a bird’s nest.” The designer’s work is purely conceptual for now, but we imagine that these beautiful clay birdhouses would sell quickly in eco-savvy neighborhoods. What do you think — would you put one of these on your roof?