Is there a source for downloadable rulesets for HIPS such as DefenseWall, GesWall, or Malware Defender? This would be a big help for noobies to use a default-deny security model. I guess the existense of a source for rulesets depends on a database of hashes (hash such as MD5, or CRC32), which would match up with the hashes of the current system's files/programs. Alternatively, imagine Malware Defender with a hypothetical subscription to Secunia for 1) applications whitelist 2) operating system components whitelist 3) and custom rulesets for applications and OS components with security vulnerabilities. Adblock Plus has a rules subscription, so why cant a HIPS? So you might have 500,000 windows system file hashes. That's nothing! Hash matching would be pretty speedy considering you would only have so many hashes per filename, and then a certain rule applied according to the corresponding hash match.