What you ask for, Kevin, may already be present. To some exent it depends
upon the user's mail system an personal preferences. Last time I checked,
the options, setable by the user, were:
DIGEST
DIGEST MIME
DIGEST HTML
DIGEST MIME HTML
Personally, with my preferences (including email system) I have no use for
anything other than plain DIGEST, but some like the other setings, and
some curse them to the bad place.
Douglas Winship [log in to unmask]