The Power Commute is a standard Timbuk2 messenger bag, but it comes with a separate battery pack. Not available separately, the Joey T1 can recharge a wide range of devices, including smartphones, tablets, cameras, and GPS units.
The T1 can connect to your device via either USB or micro-USB. The ports are housed in a dongle that can reach any of the bag's copious compartments, so that you don't have to remove the Joey from its pouch.
One minor alteration to the bag is a fabric porthole for the T1 dongle to slide through to the laptop and tablet compartment. Using it, you can recharge those devices without having to expose them to the elements.
The back compartment is not only designed to hold your tablets and laptops, but it can unzip and lay flat so you don't have to remove any of your gear to get through airport security.