This has been suggested before....
One thread were it is suggested is:
http://shoutbox.menthix.net/showthread.php?tid=25...d=248674#pid248674
Also, in combination with certain plugins (like "NickMem" to name one) and Quicktexts you can do this...
quicktext:
/command_to_store_the_current_nick
#/nick Fred
#/me (!P)
#/command_to_put_normal_nick_back
/command_to_store_the_current_nick and
/command_to_put_normal_nick_back are the commands from the plugin. Each plugin has his own commands...
Also note that this could be annoying for your contact if you use it too muc. Also there is a limit on the times you can change your nick per minute. This is a serverside limit...
/ 
