A couple of versions of Ubuntu ago, (guessing about 10.10, no later than 12.10) I used to open Nautilus, type in the local IP address of a Linux machine on my network, and it would pop open a box asking for user name and password, ask if I want to remember these credentials. Then right away I would have access to that computer's files reading and writing. I was even able to access a CD on Linux Computer #1, and play the Windows exe file using Wine on Linux Computer #2. Now I can't seem to do this on any of my recent installs. I havn't tried this on Ubuntu as I don't currnetly like how slow unity is on medium speed hardware. So I use Xubuntu 13.10 on my desktop now, and ElementaryOS Luna is what's on my laptop now.
I don't remember ever changing sharing options when it worked before, buts its possible I changed it and forgot or didn't know what that setting really did. I really would prefer a mostly graphical way to set this up. Something that is not at all dependant on distro or version, as I enjoy trying new things that come out, or even putting in one of my Old Ubuntu 9.04 CDs just for nostalgia reasons. (first version I ever used, and so easy and customizable, I really miss it :'(... )
I've heard of NFS and tried it but didn't work, and was way to text file and terminal oriented for my tastes. Want something rock solid that can't be messed up.