I thought we had a thread on this, maybe from Scoob. Mine isnt going to as long but its stuff Ive used. Please add links for useful tools. Free AV that works: Avast AVG Microsoft Security Essentials Anti Malware Tools: Spybot Search and Destroy Malware Bytes General Tools: CCleaner Defraggler Mac AV. I recommend all Mac users run AV if they forward or send anything they downloaded in an email to there Windows friends. I have not used any of these except for Clam. Sophos ClamAV also good for Linux. Avast Ill add more as I remember them, feel free to add what you use.