sshfs is a network filesystem based on ssh.
To install sshfs:
apt-get install sshfs
Add user to fuse group:
sudo gpasswd -a <user> fuse
Suppose to have a pc with a directory /home/user/shared/ to share with other PCs. The PC has address <host/ip_address>
The file /etc/fstab can be configured in the following way:
sshfs#user@<host/ip_address>:/home/user/shared /home/user/shared fuse comment=sshfs,users,noauto,exec,uid=1000,gid=1000,reconnect,transform_symlinks,BatchMode=yes 0 0
Since the mount command is not automatically executed (due to noauto option), to mount it use in the home directory the command:
mount /home/user/shared
To automatically mount the filesystem you can add the command in .bashrc file. To do not retype the password each time you perform the mounting operation you can use private and public key (see ssh).