KeyScrambler- Mozilla Add-on

Actually it is not just available add on for mozilla but it is available for Internet Explorer too!!

It scrambles the key that you had typed into the website at Kernel level.
Don't know what is Kernel? Keep reading then

The kernel is the central component of most computer operating systems (OS). Its responsibilities include managing the system's resources (the communication between hardware and software components).[1] As a basic component of an operating system, a kernel provides the lowest-level abstraction layer for the resources (especially memory, processors and I/O devices) that application software must control to perform its function. It typically makes these facilities available to application processes through inter-process communication mechanisms and system calls.

Extracted from WikiPedia
Source : http://en.wikipedia.org/wiki/Kernel_(computer_science)

So Kernel is a very important thing in computer and this keyscrambler, scrambles your typed alphabets with other random alphabets. It is much much more harder for the keylogger which tracks typed keys in Kernel. The anti-spyware software detects the keyloggers provided it "knows" that is a keylogger.

KeyScrambler is different, regardless of keyloggers existence it will still scrambles the typed keys until Kernel level.
Download it here