My church has a person clean them and take to a free clinic for reuse,
They are great for turning into travel sewing kits or 1st aid kits.
I save the see through ones for storage, glue sticks go into the very tall ones that i get from my veternarian, safety pins, buttons, and common pins...when i got to my grand daughters recitals i carry the tine spools of threads, needles...a needle threader and bring it for costume disasters...came in handy last year.
I have a ton of these too. I've used some to store change in the car, seeds, beads, bobbins, matches, and, put little rocks in one for my kitties to roll around and play with. I would welcome more ideas as well.
I use them to hold my ear buds so the don't get tangled at the bottom of my purse. I like the mini first aid kit idea.
They are great for saving seeds for next years garden.