Good tutorial for GRE Tunneling setup

Hello,

I was wondering if anybody know of any good GRE Tunneling setup tutorials that you used and works? I looked at BuyVM's GRE Tutorial (http://wiki.buyvm.net/doku.php/gre_tunnel) and it somewhat worked, but when trying to connect to the Minecraft server, doesn't work at all.

I'm tempted to try again using the same tutorial to see maybe if I missed a step or did something wrong the first time. But I would like to compare the tutorials that you have used. When trying to google...

Good tutorial for GRE Tunneling setup