Attachments don't work well with digests, which is the primary reason I don't
allow them, based on the kind of list I run, of course -)

If they are binary attachments, the user can attempt to look at the raw message
source, manually extract the attachment and save to a separate file and then
use something like MUPACK or winzip to extract the file.

If it is multi-mime enoded forwards, pretty much just read the raw email then.

Randy