1. A security system for scanning content within a computer, comprising: a network interface, housed within a computer, for receiving content from the Internet on its destination to an Internet application running on the computer; a database of rules corresponding to computer exploits, stored within the computer; a rule-based content scanner that communicates with said database of rules, for scanning content to recognize the presence of potential exploits therewithin; a network traffic probe, operatively coupled to said network interface and to said rule-based content scanner, for selectively diverting content from its intended destination to said rule-based content scanner; and a rule update manager that communicates with said database of rules, for updating said database of rules periodically to incorporate new rules that are made available.