The cardboard box - the best present for a child - better than the toy it comes in.
I immediately thought of a childhood memory. My parents got a new appliance -- honestly cannot remember what it was - but it came in a huge cardboard box. Could have been a fridge as it was that big. We had that thing all over the yard - some of us kids climbed in it and shut it up while a group would push it around the yard where we would tumble inside.
We climbed ontop of it and in it and made believe it was a house, a car, and a ride. Until we ultimately destroyed it. The best though was the tumbling inside being tossed around without knowing where you were going.