That is a very good tip since it does stop 
certain types of asynchronous popups (the kind 
you get even when you're not visiting websites), 
but it dosn't work on the popups you get on 
Animanga. Also, for Win2K users, its location is: 
My Computer->ControlPanel->Administrative Tools-
>Services-> Disable the Messenger service...
As stated, there's really not much in the way of 
drawbacks by doing this tweak.