I have a pair of sweatpants that fell down if I put anything in the pockets. The elastic is worn, but more importantly the drawstring had somehow come out.
I found a long shoelace and managed to string it through by taping it to a knitting needle.
I have therefore kept one (1) pair of sweatpants out of the landfill.
Really, I deserve a Nobel for this.
(The knitting needle was @htdrake's idea, but taking credit for a woman's work would be on-brand for a Nobel.)