ThreatFire, features innovative real-time behavioral protection technology that provides powerful standalone protection or the perfect complement to traditional signature-based antivirus programs.
ThreatFires patent-pending ActiveDefense technology offers unsurpassed protection against both known and unknown zero-day viruses, worms, trojans, rootkits, buffer overflows, spyware, adware and other malware. More Info »
This software is a perfect addition to classic anti-virus tools like Avira AntiVir Personal - Free Antivirus. You cant use ThreatFire as your only anti-virus solution, but it this a very good free enhancement to free AV tools, who cant detect what ThreatFire can, because ThreatFire works differently with a behavior-based protection. ThreatFires ability to block installation of malware strictly by identifying bad behavior is phenomenal.
Take a look at these Youtube videos explaining ThreatFire: