Round Board

There is a variant of go played on a round board. Apparently it was introduced at a European Go Congress a few years ago: (dead link)

http://www.escape.de/users/shusaku/euro96/issue3/roundgo.htm

The board is an interesting spiral. A printable board can be found in PDF here:

http://www.youdzone.com/go.html

Some more mathematical information can be found here: (dead link)

http://www.leipzig-go.de/gitter/index_e.html