Automatically processing plain text attachments

[Richard Lawrence <richard.lawrence@berkeley.edu>]

Hi all,

[I'm new to the list, so apologies if this is a rather newb-ish question.
I looked in the manual, and tried to search the archives at Gmane, but
didn't come up with much, perhaps because I'm not exactly certain which
terms I should be using.  Pointers to documentation of all kinds would
be greatly appreciated...]

I'm hoping I can solicit a little advice about how to pull plain text
email attachments off of a subset of incoming messages and do some batch
processing on them, without seriously slowing down the rest of my mail
reading.

The background: I am about to begin teaching a writing-intensive course.
Students will email me their papers every week.  I have no desire to
download, print, and read a bunch of .doc files by hand every week.  So
I am considering asking my students to email their papers in plain text.
I would like to then apply some automated processing on my end that
would:

- download each student's paper 
- apply some (hopefully) simple transformations on the text
- save the resulting document in my "teaching" directory

The goal is to have these papers end up in Org mode format, so I can do
further batch processing that will export them using LaTeX, add them to
my to-do list, etc.  Since I will have about 100 papers to read over the
course of this semester, it seems like automating this is the right way
to go.

I currently use a very simple Gnus setup.  I am running Gnus 5.13 in
Emacs 23 on Debian.  I read my mail over nnimap.

Here's what I was thinking might work: 

1) Tell my students that they must indicate in the subject line of their
email that it contains a paper submission, so I can split those emails
to a special group using nnimap-split-rule.

2) Somehow, further process the emails that end up in that group.  For
example:
 - the group could represent a local Maildir, and I could have a cron job
   process new emails found there
 - the group could represent an IMAP folder, and when I read articles in that
   group, Gnus runs a hook that extracts attachments, processes them
   in a temporary buffer, and saves the result to a file (or perhaps
   refiles in an existing Org file)

Perhaps my question boils down to: what hooks are available in Gnus that
would allow me batch process the full content of these paper-submission
emails at the time they are split from my inbox (without having to
download the full content of *every* mail, e.g., by setting
nnimap-split-download-body)?

Thanks so much for any advice you can offer!

Best,
Richard