Pages focusing on different rule sets for the game of Go.
Note to beginners: if you just want to learn to play go, please first turn to the links given under Introductions. The pages listed below usually require a good knowledge of go rules - they discuss some subtle issues related to differences between rule sets. I guess one can say that most go players actually ignore most of these subtleties, without any damage to their playing strength.
"Logical Rules", and a few links.
A collection of go positions which "challenge" rule sets. See http://harryfearnley.com/ for further links
Among other things the page contains extensive remarks on go rule sets and strange positions. Really worth reading, if you are interested in these things. In French.
An extensive set of pages where subtle questions related to the rules of go are discussed.
... by W. Hansen.
This page (part of the site of the British Go Association) shows differences between rule sets in a table and discusses some of the issues, so that it's easy to get an overview.