OK, so it does look suspiciously like one of those Mattel (NYSE:MAT) handheld football games that got taken away from you regularly during homeroom in the eighth grade. But Sony's (NYSE:SNE) now uncorked 20-gigabyte MP3 player has unique potential. While it may not be the long-awaited, silver-bullet iPod killer, it could at least eat into the gigantic market share that Apple Computer (NASDAQ:AAPL) currently enjoys in that particular -- and particularly profitable -- category.

I've not yet laid my hands on one, but according to CNET (NASDAQ:CNET), the device -- which made its retail debut earlier this month at a list price of $300 -- weighs in at just 5.2 ounces and sports dimensions smaller than those of an iPod with comparable storage capacity. It goes by the not-so-catchy, vaguely Bladerunner-esque handle of NW-HD5.

And get this: While Apple claims a battery life for its 20-gig iPod models of up to 12 hours, Sony's new device can reportedly keep on keeping on for up to 40 hours.

Energizer Bunny: Eat your battery-operated heart out.

Regrets? Sure, Sony should have a few.

You're free to port over as many MP3 files as your hard drive currently holds -- up to the player's storage capacity, of course -- but this gadget will only play the purchased, "digital rights management" (DRM) downloads offered by its corporate parent's Connect music store.

Moreover, the thing ain't exactly what the pros like to call feature rich. You can't use it to tune in to your favorite radio station, for example, and there's no built-in voice recording capability, either. If you opt for one of these puppies, you'll have to consign your spontaneous flashes of brilliance to a nearby napkin.

Still, based on its reported battery life alone, the NW whatchamacallit ought to pique the interest of portable music fans everywhere, all the while causing the fat and happy execs over in Apple's iPod division to wring their hipster hands, if only just a little.

Transistor radios with earpieces notwithstanding, after all, Sony basically invented the concept of portable music with its Walkman. Could it be they're about to reinvent it?

We -- and Apple -- shall see.

Shannon Zimmerman loves his iPod -- and a little healthy competition. He runs point on The Motley Fool's Champion Funds newsletter and has a massive collection of vinyl records. OK, maybe massive is overstating it. Shannon doesn't own any of the securities mentioned above, and the Fool has a strict disclosure policy .