I don't plan on pimping every new iphone or apple accessory here, but this looks interesting... Ars has a review for the Incase Power Slider battery backup for iPhone 3G. It's like a thick case for your iphone, but it has extra battery charge. Hit the article for pics and review. Might be worth the $$..... I already have a thick case on my phone, assuming this doesn't make it too much larger, or unreasonably heavy that is.