hmm... you could play Heroes of Might and Magic 2. That's an awesome old-school strategy game which I think is extremely fun to play multiplayer. But that game could just as well be played on a single computer in hot-seat mode, so you might want to not bother with networking it. There is one advantage to playing it on network though: on network you guys can keep all your actions in secret from each other, whereas in hotseat you get to watch everything the other person does. I've never tried it on network though, not sure how well it supports it.