Smartphones and tablets run out of juice pretty fast these days, and if you want to keep all of them charged you'll need a battery pack that can give you enough backups.
Limefuel's lineup of backup batteries is this 24,000mAh battery pack. While it is heavier than tiny batteries, Limefuel's pack is surprisingly not that big. It has enough to give your iPad a full recharge, twice over.
It's also got a pair of 2.4A USB ports so multiple devices can share in the extra power at the same time. The $150 backup battery will take a long time to fully charge. [
Limefuel]