Have you ever stopped to think about how great batteries are? As I write this a battery is powering my computer and sitting next to me on the table are two other computers and a phone which only work because of batteries. That drawer over there has four (I repeat, four) remote controls which all need batteries to do anything. If I want to go anywhere in my car it is the battery which gets thing going - no battery, no drive.
In the future all of our houses will be powered using sunlight and fancy batteries. Holy shit batteries are cool. Some of them even look cool.