Here's the Contacts editor on Haiku, BeOS' spiritual successor which is actually just a file manager window with a specific set of attributes displayed.

— https://twitter.com/waddlesplash/status/1224119010482171904

• filesystem could "just" store data blobs with user-defined metadata and custom (materialized) views
• querying could be done one level "higher" - no need for folders and files
• folder and file UI could be just one of the views on top of that storage
  • I could as easily ask for last n images, everything linked to idea of memex etc...
  • spreadsheet-like interface could be interesting as well here
  • this gets even more exciting when combined with plan9 vision where everything is a file

• computation as database retrieval (also viewing and filtering)

— Metaphor in User Interface Design - https://web.archive.org/web/20170715052154/https://courses.cs.washington.edu/courses/cse595/98wi/metaphor.html