Wireless Mouse (Keyboard) Batteries

I have a love/hate relationship with my wireless mouse (and keyboard). The mouse seems to eat batteries. It seems like the mouse needs 2 AA batteries at the most inopportune moments....

Mouse:
September 27, 2007
August 25, 2007
July 28, 2007

Update August 25: The mouse needed to be fed again.
Update September 27: Fed mouse again, keyboard has shown an alert. Looks like the mouse needs to be fed once a month.