From AVAST Software:
Avast Mac Security (formerly Avast Free Antivirus for Mac) offers three shields,on-demand scanning and WebRep clients which are automatically (optionally) installed to Safari, Chrome and Firefox browsers. Our Web Shield and Mail Shield combine to check the vast majority of incoming data from the Internet, while File Shield scans all programs stored and executed from your hard drive. Everything is packed in a brand new GUI.
What's new in this version: