To Bateluer:
Well, I seem to recall some people saying in forums that they can go several months with their mouse without changing batteries, but I could be wrong. I'd say my mouse gets used a good bit more than the keyboard so I guess I should expect a shorter battery life with it. And, maybe I have some habits that contribute to this; for one thing, I often move the mouse pointer along text just as a way of pointing at the text while reading it. Still, I think about the longest time I get from a pair of batteries is about 2 1/2 - 3 weeks if I deliberately try to use the mouse less. I really thought that time should be longer.
But, compared to your experience, it seems like my mouse may actually be doing OK. My mouse model is simply the Cordless Click! Plus.
I do use rechargeable batteries.