Being one of my favorite hobbies, Go is a beautiful, elegant “martial art” in form of a board game. Here are some useful links to know Go better and start playing.
What is Go: http://www.britgo.org/intro/intro1.html
Interactive Go tutorial: http://playgo.to/iwtg/en
Playing Go vs other players: http://www.gokgs.com
Go problems: http://www.goproblems.com
Go lessons: http://www.internetgoschool.com
Go Wiki: http://senseis.xmp.net