On computer #1:

1. Enable the eth1394 module blacklisted in /etc/modprobe.d/blacklist:
   
   Code:

   sudo gedit /etc/modprobe.d/blacklist

   and put # before "blacklist eth1394" to comment the blacklisted module (so that it can be loaded at boot).
2. Load the eth1394 driver:
   
   Code:

   sudo modprobe eth1394

   You can see whether the module is running:
   
   Code:

   lsmod | grep eth1394

3. See the list of network interfaces:
   
   Code:

   sudo ifconfig -a

4. Assign an IP to the firewire interface (for me it's eth2):
   
   Code:

   sudo ifconfig eth2 192.168.200.1 up

Repeat the above mentioned steps on computer #2:

1. Code:

   sudo gedit /etc/modprobe.d/blacklist

   and put # before "blacklist eth1394"
2. Load the eth1394 driver:
   
   Code:

   sudo modprobe eth1394

3. See the list of network interfaces:
   
   Code:

   sudo ifconfig -a

4. Assign an IP to the firewire interface (for me it's eth8):
   
   Code:

   sudo ifconfig eth8 192.168.200.2 up

Please note that the first computer uses IP address 192.168.200.1 while the second one uses IP address 192.168.200.2.

After that you should be able to transfer files between your computers with samba, FTP, SSH, NFS, ...