After Allison and I got the Wii we went through tons of batteries. And now with a baby on the way we are going to have to get a battery or two or six for every item that comes through our door. I was looking at the things I still need to put together, the baby swing, the baby bouncer and then the toys that make the noise. Each one is going to be battery powered. So the best accessory that we ever got for the Wii was a battery charger, I am going to have to invest in more rechargeable batteries and chargers of various sizes for the coming years.