In the trunk of the Model S there is a storage compartment where the optional 3rd row seats stow away. Wouldn't it be cool if there was an option to have that compartment converted to a 2nd battery location? Maybe a modular battery back - since lifting up and placing a battery pack that size would be way too heavy. Seems like the space there and the current size of the battery pack - you could maybe add an additional 10kw of battery. It would be perfect for road trips where range might be an issue. Even an extra 30 or 40 miles of range could make it worth it. And the total weight probably wouldn't be more than having a backseat passenger. Then of course you have the little cubbyhole area in the the frunk. Even for just a couple thousand - I think there would be a market for it. Seems like cooling might be an issue - but probably could be resolved. Has anyone else thought of this?