All Firefox users check this out, and also check your browser settings for it
The FormSpy trojan was discovered on July 25 2006 and appears to be a malicious Firefox extension which steals sensitive information.
It is labeled as a numberedlinks extension.
See the Mozilla site http://numberedlinks.mozdev.org/
McAfee site http://vil.nai.com/vil/content/v_140256.htm
If you have this in your extension list, remove it.