flase block storage

so we all have those inventories of items we want hidden a bit more safe than in a hidden room right. well what if a block like cobble stone or stone bricks also had a another functionality to them where instead of just having it be a normal block it was a chest hidden in disguise as a block like that the same was a book might be hollow inside to hide things. it could be placed on a wall just like a normal block but it really is a chest in plain sight hidden away undetectable by those who do not even know its there.