Goban is a Chinese game of Go simulator which can be played either single player (against a computer), against a friend on the same computer, or online against people all around the world. The difficulty of online play is quite steep, with almost all registered players having a rank of at least 1d+.
People You Should Play Against Edit
GameFAQs name - Goban name/rank
Chumbucketeer - Zakamaga/beginner