One of the use cases for Beagle being currently considered is as a backend to music/media player applications. An existing use case that many of these apps tend to handle badly is the support of generic MP3 players without indexes (i.e. not the iPod because it has a song db, but players like the iAudio M3). Specifically, as these players will often be plugged/unplugged relatively frequently, existing metadata caching methods fail (both because of changing root paths, and that a temporary lack of a player tends to get the data deleted), and this combined with the usually slow hard drives in these devices, results in a considerable amount of activity to re-index them every time they're plugged in, plus a significant delay before songs are findable. Target player will preferably need write access, but this will work without (and so works to some extent with media like CD-Rs)

Proposal is as follows:
1) Create a separate beagle db file for each external media device, stored according to HAL device name, but searchable in a unified way with the existing db. Allow switching on/off this option for all devices (present and future, without knowledge of what might get plugged in in the future) by a simple addition to the config file.

2) In the event that writing to the device is possible, keep a copy of the db as a hidden file on the device. When a new device is plugged in, check for a newer copy of the db on the device before searching for one on other local storage.