If you have a directory that has lots of articles in separate files in it, you might treat it as a newsgroup. The files have to have numerical names, of course.
This might be an opportune moment to mention ange-ftp, that
most wonderful of all wonderful Emacs packages. When I wrote
nndir, I didn’t think much about it—a back end to read
directories. Big deal.
ange-ftp changes that picture dramatically. For instance, if you
enter the ange-ftp file name
/ftp.hpc.uh.edu:/pub/emacs/ding-list/ as the directory name,
ange-ftp will actually allow you to read this directory over at
‘sina’ as a newsgroup. Distributed news ahoy!
nndir will use NOV files if they are present.
nndir is a “read-only” back end—you can’t delete or expire
articles with this method. You can use nnmh or nnml for
whatever you use nndir for, so you could switch to any of those
methods if you feel the need to have a non-read-only nndir.