Never a bad idea to sign or encrypt your email, especially if it’s free. I don’t know about giving your personal information to a company called Comodo though

Of course, you haven’t anything to hide, right cupcake?…Sorry, I was just watching “Prison Break”

SSL Certificate Authority Digital Certificate SSL Apache Server Certificate

Other Certification Authorities sell Digital Certificates for email for $19.95! There is no cost for a Secure Email Certificate. Free for personal use only

(Thanks Mike)