Last year I bought a Mac Mini with the intention of using it as the front end for a media centre solution.
For my plan to work, I needed to share my media from the FreeBSD server to the Mac. Considering both of these operating systems are *nix based, I decided to go with the triied-and-tested NFS to do the sharing.
So, on the BSD machine, edit the file /etc/rc.conf to include these lines:
rpcbind_enable="YES"
nfs_server_enable="YES"
mountd_flags="-r"
nfs_reserved_port_only="NO"
This will enable the NFS server on boot. The nfs_reserved_port_only line is especially for OSX that likes to use ports above 1024 for NFS!
Next, edit /etc/exports to list the shares and also who is allowed to mount them:
/store/media -ro 192.168.1.0
This line configures /store/media to be mountable by clients, allows them to access it ReadOnly and allows access from anybody within the given address range 192.168.1.x.
If you change your exports file, you need to run the following command to allow the system to re-read the file:
/etc/rc.d/mountd onereload
There are several other options you can use (-maproot etc), which you can find from the FreeBSD handbook NFS page.
On the Mac it was quite simple to mount the share. Open finder and from the top menu Click Go > Connect To Server….
In the dialog that appears, type in the location of the share. In my example this would be:
nfs://192.168.1.1/store/media
OS X should make a pretty icon on your desktop for the share (and you can find it mounted in /Volumes too).