"Clamav is the most popular free anti virus program for Linux environment.( Of course it scans for widows virus) However, clam is a command line utility and you need some skills for manipulating is properly. There are several graphical front ends for clam av which can make your life easy. The most popular among them are clamtk and Klamav.
"Clamtk
"Clakmtk uses Perl-tk for GUI. It is available for several distributions. On ubuntu you can install it as
$ sudo apt-get install clamtk
"On Karmic it showed up as virus scanner under Applications ->system tools.
"On launching it , the following screen pops up"
