it would be good to have a package for a virus scanner. What do you think about clamav? Why don't include it by default? There are also GUI tools like clamtk and file manager addons like thunar-sendto-clamtk (XFCE) or nautilus-clamscan (GNOME) which are very useful for Linux newbies. Overmore I think, an e-mail scanner like clamsmtp, clamassassin or claws-mail-clamd-plugin would be fine.