KeyScrambler Personal encrypts your keystrokes at the kernel driver level to protect your information from keyloggers

https://addons.mozilla.org/en-US/firefox/addon/3383

Keyczar is a cryptographic toolkit that supports encryption and authentication for both symmetric and public-key algorithms. It addresses some of the aforementioned issues by choosing safe defaults, tagging outputs with key version information, and providing a simple application programming interface. Keyczar's key versioning system makes it easy to rotate and revoke keys, without worrying about backward compatibility or making any changes to source code.

 http://www.keyczar.org/