While XMMS doesn't have heirarchical playlists (a real bane to those who organize by album), you can add some organization by creating spaces or dividers between playlist items. This is most useful when sorting by filepath and filename (default). I have my untagged vorbis collection organized by "artistorvarious - album/trackno. artist - title.ogg" and this helps prevent the album items from running into each other (screenshot).
To do this, create an empty file and encode it into a format that XMMS understands. Then you can rename it as " " for a space or "-----" for a divider, or something similar. Then you can stick it in the album folder and depending on how you named it, will go in front or behind all the folder items in the playlist. For example:
$ touch dummyfile
$ lame -r dummyfile " "for a spacer, or:
$ touch dummyfile
$ oggenc -r -o "-----------" dummyfile
for a separator.Mac OS X Hints
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