Dec
Antidote Super Lite version
Freeware lite version of the commercial Antidote program. It utilizes the same virus database as the commercial version.
Avast!
Anti-virus program for Windows. The home edition is freeware for noncommercial users.
AVG Free edition
Free edition of the AVG anti-virus program for Windows and Linux. Tested and recommended by Freebyte.com.
Avira Antivir
Free anti-virus software for Windows, Linux, Free BSD and Solaris. Detects and removes more than 50,000 viruses. Free support.
BitDefender
Freeware virus scanner for Linux.
Clam AV
Freeware, GPL, Linux. Clam AntiVirus is a GPL anti-virus toolkit for UNIX. The main purpose of this software is the integration with mail servers (attachment scanning). The package provides a flexible and scalable multi-threaded daemon, a command line scanner, and a tool for automatic updating via Internet.
ClamWin
Freeware, open-source anti-virus program for Windows.
Comodo
Anti-Virus Free anti-virus program for Windows.
Cyberhawk
Protects against viruses, worms, trojans and other spyware, designed to be a complement to your current anti-virus software. Cyberhawk does not need to know anything about a virus before it can protect you against it. This is because Cyberhawk looks at the behaviour of an infected program (instead of the contents of the infected file). The basic version is free.
FProt
Free anti-virus software for Linux, FreeBSD and DOS (personal use). Evaluation version for Windows.
HandyBits
Free for personal use. Virus ’scanner integrator’. After performing an auto-search for installed virus scanners, it will scan your files using all found installed virus scanners. This can be useful, since some antiviral programs are good for one type of viruses, other programs for other viruses.
PC Tools AntiVirus
Free anti-virus program + firewall for Windows.
Source: http://www.freebyte.com/antivirus/.