Yes, of course! Linux users may not be affected by common malware, but we should all do our best to protect information assets and IT infrastructure.
The one I have tested thoroughly is F-PROT Antivirus for Linux. It works really well on Ubuntu workstation and server. Here's an example of a neat setup, useful for both home and corporate situations.
Example 1
Ubuntu server, serving a NAS via Samba shares. Accessible to both Linux and Windows hosts. Run F-PROT as a cron job on the Samba shares, and scan for malware.
Example 2
Ubuntu server as a backup server, storing complete home directories from Linux hosts (rsync) and Windows hosts (Cobian). Run F-PROT as a cron job, scheduled with respect to backup jobs. You can easily set up a cron job to do a weekly scan for adware on Linux backups, and a daily full heuristic scan on Windows backups. F-PROT is really light on resources.
F-PROT Antivirus for Linux is free for home users, and if you need it for Windows or if you are a corporate user you can get F-PROT quite cheap at shop.arbisec.com.