An English networking siite.

http://asoboo.com/

Korean heavyweight Cyworld has also set up shop in Japan.

http://jp.cyworld.com/

The most popular networking site in Japan. However only in Japanese and you can only become a member by invitation only.

http://mixi.jp/

Japanese version of their insanely popular social networking site.

http://jp.myspace.com/

“Japan's First Family Network” and is targeted specifically at English-speaking families living here. Meet other families, talk shop and share advice about how to get the most out of life in Japan.

http://piqniq.jp/