I use Path Finder for some fancier features, but since upgrading to Lion, I could not see my Linux SMB server in the side panel. After waiting for their Lion patch with no change, I figured out a very simple solution.
For whatever reason, Path Finder can't find or list Samba servers like it did in Snow Leopard. But, if you either install or modify an Avahi daemon on the SMB server, and advertize SMB services, Path Finder will see the server again.
After installing the Avahi daemon in a manner appropriate for your distribution, just create and save this simple file to /etc/avahi/services (on the server):
<?xml version="1.0" standalone='no'?> <!DOCTYPE service-group SYSTEM "avahi-service.dtd"> Samba Shares on %h _smb._tcp 139
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