same as other games for instance:
http://www.hotkeynet.com/wow/wow-sam...ur-on-two.html
could be a starting point
(though I would start from my set as the key bindings are closer/better
http://www.smileyouareontv.com/softw...tkeynet-script
and just use Send your2ndpcIp instead of local for the 3rd and 4th window)