Rubber Band Ball
I was once a postman for four months. It was not a happy time. I ended every day with pockets full of rubber bands from the bundles of post I had delivered. Each day I took them home and added them to a gradually growing rubber band ball. It made me feel a little better; like I was taking something back.
By the time I left, the ball was seven inches in diameter.
Over the past fifteen years, it has gradually decomposed, occasionally pinging in the corner of the room as it sheds its layers, undoing the tension from which it was made.