Oh my! We are in the same with the toothbrushes. Though I only have 5 here I planned to use them to clean our rest room as we change toothbrushes every 3 months. Haha I never had the chance to change the toothbrushes that I hoard and just remember them after reading this post.
With the mindset that I can use them again for future like the water bottles, vinegar gallons (for a pot project planning to repurpose them as a vase haha) they are stocked now in our home waiting for their time to resurface.
I use them for similar things but I guess the amount of them I was saving just kind of got out of hand :)