Played through the original .hack series (Infection/Mutation/Outbreak/Quarantine) and .hack//G.U. Still waiting for the .hack//Link to come to the US. I have the dvds for .hack//Sign, Legend of Twilight, and Roots. Also have most of the mangas and novels.
It was the inspiration for Worlds Within Worlds
. I'd like to create more material to expand on the setting I created in that book but alas I haven't had the time.
The best thing about the game was the immersiveness. The characters were interesting and I wanted to know their story. In general I thought the original games did a better job on the characters but G.U. had better forums.