ThreatFire provides immediate protection out-of-the-box. There are no difficult configuration decisions, intimidating messaging, or time-consuming signature downloads. The easy-to-use program with its ActiveDefense™ technology does it all so you don't have to.

Traditional antivirus software offers strictly reactive protection. It can only protect you from a new threat after the threat has been discovered and new signatures to protect against it are developed, tested, and then released for download. ThreatFire does not rely on signatures to protect you; instead, it uses intelligent behavioral analysis to proactively hunt down and paralyze any activity or behavior that might compromise the security of a PC.

http://www.threatfire.com/download/