A couple months ago, I was working from home on a Friday. My mom was here, and I ran down to the mail room to pick up a couple packages. Within ten minutes, W had a hold of one of them and he was mesmerized. A little explorer, looking in and out of the boxes, holding them over his head, putting things in and taking them out.
The box fascination has continued. I try to keep most of his toys in or around boxes for an added layer of curiosity.
Oh, and I love watching him. With a box. In a box. Outside a box. Next to a box.