By graphic adventure, I mean point & click LucasArts-type games.
Those games have a mostly linear structure in nature, and usually don't offer as many variants as other games types like action, rpg, strategy, which makes this genre difficult to implement a multi-player feature.
I'd like to know if there has been any attempts on doing such a thing, and if it would be viable, as players going offline or leaving a game in the middle would affect significantly the other players' game.