I was just taking a shower and thinking about the battery life of the PSP and I thought, what if you could put two batteries in at the same time. Then I thought, wait... if you can do that, why not just have expansion slots like a laptop for multimedia devices. That would be pretty cool. Able to add two batteries to the handheld, or a MP3 player, or whatever you see fit, this would keep initial system costs down and would allow you to buy only what you needed. Probably would never happen, but sounds cool to me.