This is an improvement request to add some filtering options to the "Dashboard Administration" page:

  - Add an input box that allows filtering of the dashboard list by username.
  - All of the "default" (non-public / non-shared) user dashboards are filtered from the list initially, but allow them to be displayed by clicking a button/checkbox/tab/whatever.

This will help make managing dashboard permissions and sharing much easier than wading through numerous pages of dashboards from hundreds of users, especially considering most dashboard management is done on public/shared dashboards.