Moon Secure Antivirus aims to be the best Free Antivirus for Windows under GPL license. It offers multiple scan engines, Net shield, Firewall, On access, on Exec scanner and rootkits preventions plus features from Commercial Antivirus applications.
Moon Secure AV is an opensource antivirus currently using the clamav engine due to fast response time and huge AV database, however we are implementing another engine that is heuristic and will allow users to customize the engine on the fly.
Unlike CLAM it has an enterprise level real-time scanner. It is built for windows and will run on XP and vista. It can scan portable drives and fixed drives. It is able to Detect viruses, Trojans and spyware.
Moon Secure Antivirus was designed to be a simple, open source antivirus scanner.