Web Defender - extension for Google Chrome™
Real-time protection for your browser
Can block malicious domains, malicious URLs, phishing websites.
Contains expanded database of malicious domains and URLs.
Contains integrated module "Smart Phishing Detector" for accurate detection of phishing websites.
It's absolutely free!
"Enigmail is a security extension to Mozilla Thunderbird and Seamonkey. It enables you to write and receive email messages signed and/or encrypted with the OpenPGP standard."