Ok heres the step by step, and this was researched by me so that way I can make a healbot that heals me as I run around. *yum*
How to do it:
Install a fresh copy of WOW, make up some random folder to put it all in.
Get a port forwarder/program or firewall.
Rename the newly installed wow.exe to wow2.exe (or whatever).
Setup your port forward so when wow2.exe runs forward incoming ports to => XXXX *make up the port you want to send it to*
Log on two accounts OR log onto the same account and get the Debuff named -Evil Twin-.
works and is a resource hog just fyi.