What personal belonging would you choose to include in a time capsule to be opened a century in the future?

If given the opportunity to encapsulate a personal item for posterity, I would choose to include a detailed journal. This journal would not only document significant life events and experiences but would also encapsulate my thoughts, reflections, and observations about contemporary society, technology, and global issues. My intention would be to provide a snapshot of life in the early 21st century from an individual perspective, something that can often be lost in broader historical narratives. Alongside personal insights, the journal would contain sketches and photographs to offer a visual standpoint, and perhaps even snippets of popular culture references, like song lyrics or news clippings, to add context and depth. Such a contribution could offer future generations a more nuanced understanding of our time, much as diaries from the past have enriched our grasp of previous centuries.