Well-known notebook bag maker Targus introduced the SonicPak at CES 2008. This knapsack PC carrier features a detachable outside panel with dual planar speakers, and a built-in battery-powered amplifier. Plug its cable into any audio device that accommodates a headphone jack, and presto! you’ve got a surprising amount of sound at your disposal.

The bag incorporates NXT’s flat speaker panels, integrated right into the top surface of the bag’s detachable outer panel. The amplifier and cable are accessible through the rear, well away from the elements to which the outside surface will be exposed outdoors. The speaker panel is secured above with two snap-in clips, and below with a zipper that run across its entire bottom edge that mates up with the bag. Power comes from three AA batteries, which crank out sound levels well beyond what built-in notebook PC speakers can deliver. At top-volume, I was uncomfortable sitting a scant four feet away from the speaker panel on the other side of a coffee table in the Targus demo suite, with the Red Hot Chili Peppers blasting away.

The speaker panel is also covered with a layer of waterproof ripstop nylon that enables its wearer to take it out in wet or dry weather. The panel also floats above the bag’s outer surface, and is thus well-suited to secure a jacket or something else that its carrier wants to attach to its outside. On the inside, the SonicPak is a typical Targus PC bag: sturdy and well-padded with a notebook holder, numerous other pockets, and zip-out access to a workspace area where its carriers can tuck pens and pencils, various notebook accessories, a cellphone, and other odds and ends. The bag offers a little less interior space than other Targus PC knapsacks, because the rigid outer speaker panel perforce limits its expandability, but buyers interested in its acoustic properties are likely to be OK with making such a tradeoff.

The bag comes in a muted but attractive black-and-grey color scheme, and a suggested retail price of around $100. Expect this item to become available between March and June of 2008, for sale at the Targus Web site and a Best Buy near you.