I use old Christmas cards and greeting cards to make small boxes to use for gift giving those little items that always get lost.
Worked in a computer tech dept and parts came in very sturdy ziplock bags. I made everyone save them for me, so now I have large bags for my quilting projects. Holds fabric and pattern/book all together till I'm ready. Left over batting and scraps go in pet beds for the local human society. I buy bulk (dish liquid, shower cleaner, cleaning supplies) and refill my smaller spray bottles.