Comodo offers free S/MIME certificates. https://www.comodo.com/home/email-security/free-email-certificate.php https://www.comodo.com/home/email-security/free-e

Comodo offers free S/MIME certificates. https://www.comodo.com/home/email-security/free-email-certificate.php https://www.comodo.com/home/email-security/free-email-certif... EDIT: A quick google showed me that there are also others that offer S/MIME for free http://kb.mozillazine.org/Getting_an_SMIME_certificate http://kb.mozillazine.org/Getting_an_SMIME_certificate