MIME-Version: 1.0
Content-type: text/html; charset=iso-8859-1
subject: test
<html>
<b>hello world!</b>
</html>
Content-type: text/html; charset=iso-8859-1
subject: test
<html>
<b>hello world!</b>
</html>
and then do this:
cat filename | sendmail -v recipient@email.com