Kotaku
Games Radar has a walk through of how to trick your Playtation 2 into letting you play Gran Turismo 4 on the Internet. To get this to work you need a PS2 network adaptor, a copy of the game, a PC with a broadband connection and an ehternet router. I'll let Games Radar walk you through all of the minutia, but I will say that the end result isn't as pleasant as you would expect. Appareantly, GT4 Online is quite jerky, mostly because the screen's redraw is dependent on network speed. I suppose there was a reason Sony released the game as an offline racer only.
Play GT4 Online Now [Games Radar]
