I think a lot about future archeologists and how their work will be very different now that a lot of things are digitalized : you won't find a lot of people writing their day to day physical diary in 2021 but we all have social media accounts that show our lives in a widely different manner! The junk mail thing is also something i think about , i'm constantly keeping museums ticketd and leaflets and receipts because...what if a future archeologists (or someone from my family) want to know what my life was like 50, 100 years from now? xD I know i was awed when i found my great-grandmother sewing kits in my family house attic. It's a everyday thing but with time...it becomes an artifact!