be aware though, that ni-mh and alkaline batteries are heavy. if i put 2 batteries in the MM, it becomes much heavier than the logitech MX1000 or VX1000.
so i generally only put 1 battery in the MM. it's the lightest battery i could find. it has 1800mAh and lasts for about a month or so (1800mAh is pretty low for a battery. most ni-mh batteries how has capacity of 2500mAh and up)