The video: Move over, Petman. The military has a new walking robot: The LS3 (Legged Squad Support System), a big, fast, "rugged" machine that can carry more than 400 pounds of supplies (without refueling) over 20 miles of tough terrain where wheels wouldn't cut it. The robo-mule, designed by the government's Defense Advanced Research Projects Agency (DARPA), is equipped with sensors that allow it to auto-correct its balance. (Watch a video below.) The machine's creators say they'll soon teach their robotic pack animal how to understand spoken commands like "stop," "sit," and "come here" — and hopefully deploy it on field exercises with Marines within two years.

The reaction: This isn't the prettiest "war horse" I've ever seen, says Tim Hornyak at CNET. "Megatron looks beautiful by comparison." And it's not "exactly ready for live action in its current state," says Ray Walters at The robo-mule prototype is brutally loud, making it awfully "hard for a unit of soldiers to not give away their position to the enemy when using it." But hey, at least it has a mobile charging station for radio equipment, phones, and iPods. "Fortunate Son," anyone? Take a look: