I bought the Battery Charger in order to keep my Magic Mouse/Magic Trackpad/Keyboard (not Magical?) from draining my wallet every 5 minutes in need of AAs. It's a neat device, looks like an product for sure. I charged the first pair and waited roughly 2 weeks to put them in the MM, but by the time I had put them in, they had already discharged to 63%! When I put those in, I went ahead and charged up the next pair. 3.5 weeks later, MM needed AAs again, so I put in the next charged pair, and these had already discharged to 66%! I realize the obvious solution is to not charge them until a day before needing them, but does anyone else notice this? Is it because I'm leaving them in the charger while it's not plugged in? And as a side note, is it ridiculous my MM has gone through 6 AAs while the batteries that came with my iMac's keyboard are still at 62%? Trackpad seems way more energy efficient than the Magic Mouse, as well.