Quote Originally Posted by boostNslide
Having to buy AA or AAA batteries or whatever over and over would suck....
I have one that takes double AA's. I just bought 4 rechargable batteries and a battery charger, and these same 4 batteries have lasted this mouse over a year already with no signs of deterioration yet.

Re: the original post... There are a couple obvious things like make sure it's an optical mouse and has a scroll wheel, but beyond that the mouse you choose is mostly a matter of preference. Do you want one that's sleek and simple? Stylish and fancy-looking? A gaming and/or power-user mouse with lots of buttons and features? Does one fit your hand better than the other? Etc... The only real advice I can offer is the brand. I personally like Logitech mice the most and have had multiple problems with Microsoft mice (but I've only owned a few mice in my lifetime, so small sample size).