An apron made from an old dishtowel and a shoe lace, both of which I packed in case a need arose. (You would have to sit in on one of my packing sessions to understand...)
It's amazing how many things you can live without for 3 months, but for me an apron is not one of them.
It's also amazing how much it can cost to buy the things you DO need for 3 months, so we are re-purposing as much as possible. My innovations with empty yogurt tubs could put the Container Store out of business!