ScamZapper is not like most other pop-up blockers, as it targets a specific kind of pop-up: the worst kind. Some pop-ups will lock up Safari, claiming that your computer is infected by a virus and you need to call a bogus technical support number for help, and this is exactly what ScamZapper is designed to prevent. This is not a virus or adware, so anti-virus or adware software won't detect it. Furthermore, even pop-up blockers usually fail to stop these.

Requirements:
OS X 10.6+
64-bit Intel