ClamWin

Website/Download: http://www.clamwin.com/
License: Freeware
OS: Windows
Latest Version: 0.95
Publisher's description:
ClamWin is a Free Antivirus program for Microsoft Windows 98/Me/2000/XP/2003 and Vista.
ClamWin Free Antivirus comes with an easy installer and open source code. You may download and use it absolutely free of charge.