The iPowerRush brings 10 to 15 hours of additional playtime to iPods and iPhones by using six AAA batteries, and provides an extra 120 hours of standby time for iPhone users. The unit features a slip design, measured at 2-inches by 3 5/8-inches by 0.5-inch, making it very compact, with a push-button that shows remaining battery power, and also features a built-in voltage limiter that prevents it from over-charging the iPod's battery. The iPowerRush is currently available for $30 from iPowerRush.com.