tedster - 7:53 am on Dec 5, 2008 (gmt 0)

I'm glad it's rare, because it sure sounds evil.

Users could be infected with the Trojan either from a drive-by download, which can infect a PC by exploiting a vulnerability in a browser, or by being duped into downloading it, Canja said. When it runs on a PC, it registers itself in Firefox's system files as "Greasemonkey," a well-known collection of scripts that add extra functionality to Web pages rendered by Firefox.