This is a semi-fringe case I think, but it would take 30 minutes for
someone who "knows the code" to add this feature (I'm guessing of course).

It might be useful to have a way to save all the attachments of a document
at once (perhaps in a folder named after the mail subject).  I do believe
the best way is to have people send zip files (or some other package)
instead of attaching a ton of documents, but seeing as how it is very easy
to just DnD multiple attachments into an email, I think it should be very
easy to save them as well.

Now that I mention it, I'd like it of received attachments were displayed
the same way as composing a mail with attachments (a little file browser
area) so I could just click on them and have Nautilus do whatever it does,
or right click....however this destroys the 'inline view', but the inline
view is less useful when you can click on an image (for example) and have
EOG display it.

Anyways, the former is the feature request, the latter comment is just an
aside :)