BeFS or BFS or other filesystem for linux with attributes on debian

[Dan Hitt <dan.hitt@gmail.com>]

BeOS had (and i imagine Haiku has) a file system that allows all kinds
of attributes to be attached to a file.

I understand it to be something like having a two-column key-value
table attached to every file.

I understand that file system was ported to linux with the name BeFS
(the Be name of 'BFS' was already in use).

However, when i search around for it, i get the impression that it it
is no longer under development, and the stable version was read-only
anyway.

So wondering if any there's any other file system around with
semi-arbitrary user settable attributes and values?

The reason i'm wondering, is i'd like to try one out to attach
metadata to files, and i'd really like this process to be just as deep
in the stack as is possible.

Thanks for any info, or corrections if i'm wrong about BeFS.

dan