I often keep a pile of books or other things on my bed that I am using, or thinking about using. And I agree, spreading them out to take inventory, or because it would look cool to see a bunch all laying out, especially those by the same author or those of a series. I did that with my Sweet Pickles books.
I used to keep the original boxes for my toys, and stack them neatly in my closet. It was more exciting to open it out of its original box, kinda like getting a new toy again. Things like the smells of rubber tires and styrofoam would accumulate again.
Then after that was over, I would take it apart, put it back together, sometimes modify it. I didn't so much build things to play with them. I built things to see if I could mimic real systems, or to run tests and see how much weight it could pull or how much or a slope it could climb with and without soap on the ramp, or how much power it could take before something broke. I used a lot of Goody hair elastics as motor belts and the smell of burnt rubberbands was pretty common in my room.
I would also sort my Crayola 64 pack a certain way, and it would bother me if someone messed with it.
In college I had my own cheap record player that I used occassionally. But more often I would pretend it was a lathe and would use a screwdriver to shave curls of plastic off the disc. It was both addicting and relaxing.
Here's what my daughter did with her Halloween candy at age 2. Part of the photo is cut off but she sorted out all the candy.
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