haha whoops...i should read your post and not other people's...
anyways, if you're looking to share your internet connection through your mac w/your ps2, you can do that. get a second network card (or if you have an airport on there, get a wireless ethernet bridge for your ps2, linksys sells some ps2/xbox sorta specific ones) for your mac, plug it into your ps2. then go into the system settings and under network, select your nic that's connected to your outside connection. select the configure this interface option and under one of the tabs there's a checkbox for uses this interface to share my internet connection...should be all set.
if you ever host a server, you'll probably need to port forward some ports to allow for incoming syn packets to be routed to your ps2, but just make your friends host it otherwise.
(my eca is kicking in so i'm all wired...if i didn't answer your question...sorry).
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Whenever I feel like unintelligent conversation w/a bunch of 15 year old brats, I go to newschoolers
I always say what I feel and that is a promise, nothing in life is above being honest - 311
from chaos comes clarity, I tell ya what you appare to me, you ought to know glycerin tears don't fool me, i tell ya delusions plaguing everybody - 311