Your world fits
in your pocket.

One library of plain folders. Copy it, back it up, carry it on a USB stick.

The library in moood: sci-fi film, music video, fantasy novel, spring collection and café logo.
In moood. Your library lists every moood by name. Click one to open it.
moood library/
  sci-fi film/
    woolworth-building.jpg
    opening-shot-a-shift-change-at-dawn.md
    rhapsody in blue, 1924.m4a
  café logo/
    design-for-a-poster.jpg
  spring collection/
    gazette-du-bon-ton-1920.jpg

On disk. The same library is ordinary folders and files. Open them without moood, copy them, back them up.

For the hardcore.

Most people use one computer. That's all you need. Otherwise:

  1. A USB stick.
  2. A folder you already sync.
  3. Your home computer, over a private network between your own devices.
  4. Your own homelab: an old laptop or mini PC, always on.