Since starting an antique box with my family odds 'n ends of genealogy treasures, I've run out of room. In fact I've filled three similar size boxes with my treasures.
What do I keep in my treasure box? Original family documents (land records, deeds, marriage certificates, birth and baptismal records, death certificates etc), family bibles and journals, WW1 paybook and records for my grandmother's brother, school report cards, wedding invitations, letters, postcards and more. I only keep original items that belonged to someone in my family, not photocopies of records I've found while researching.
You can see the blanket box I'm going to use on the left in this photo. It already had a few items in it so I'm going to have some fun going through my smaller boxes and re-organizing the items to go in the blanket box.