Moving pop-up window for gmail notifier.

I have managed to get three gmail notifiers to work simultaneously, the problem that I have now is that when I receive mail in two or three accounts at the same time all two or three semi-transparent pop-up windows overlap in the top right hand corner of the screen. Is anyone aware of a native or naturally intuitive way of moving the pop-up windows to different locations on the screen? This is not a serious problem I just like to have everything aesthetically situated. Thanks.