Last night - I was DISing downstairs in the living room, and heard a noise in my DS' room right over my head. I took the stairs 2 at a time, only to find a hardcover book had slid off his bookshelf and made the huge thud. (He never budged!)
When's the last time you had your whole house to yourself, and purposely did not use that time to do anything productive (i.e., laundry, dishes, paying bills)