Powerbag...anybody tried it?

http://www.coolhunting.com/tech/powerbag.php

Fit for arduous travel schedules and lengthy commutes, the recently released luggage line from Powerbag features an on-board charging system to keep you on the grid no matter how far from an outlet you may be. Each bag's removable and rechargeable power source comes equipped with an Apple device connector, Mini and Mico-USB cords, and a standard USB port, putting out enough power for up to four devices at once. Most importantly, the smart charge system diverts power to the devices that need it most, preventing your tablet from hoarding all the juice.
Outfitted with a removable 6000mAh battery, the bags offer enough juice to fully charge an average smartphone up to four times before the power supply needs to be refilled. Both packs feature a small AC adapter plug on the outside that connects to any wall outlet for easy recharging. The Business Class Pack and the Instant Messenger bag sell for $180 each directly from Powerbag online. Other styles are also available, and smaller chargers are available at a lower cost.

Seems pretty sick.

Seems good for charging phones, not sure how relevant this is to DJing though.