What happens when Javascript and the Windows hosts file collide...

Simple Pharming - 0x000000 The Hacker Webzine

There is so much you can do with Javascript that the best way to describe the toxic mix of browser exploits with Javascript will be an example to launch a pharming attack. The sheer beauty of pharming is that the surfer will almost never know that he has been compromised, because it is very silent. One way of quickly pharm surfers is to modify the hosts file on Windows.
Read the rest for the sample code. Firefox + NoScript for me, thanks.