Surely by now you've seen the video of the "Big Dog" -- the amazing quadruped robot designed to serve as a "pack mule" for soldiers in terrains where military vehicles are unable to manage or maneuver. I'll wager, however, you've never seen the original "Beta model" in action?Many who have seen the Big Dog in action have commented on how lifelike its motions are. The legs move with an almost deer-like quality. Those that watched the video saw the robot compose itself on ice-covered ground and regain its footing after being pushed by one of the testers.

While the...ahem..."Beta" in the video below isn't quite as solid on its feet, it's clear that this incarnation has even more of an organic look and feel to it than its successor. Just take a look:

OK, joke's over, son. Actually, this parody of the real Big Dog was created by some clever folks in Waltham, Mass.

Clever folks with black spandex. Yikes.

One final word on the real deal -- Gizmodo recently called the Big Dog "The Future AT-AT of the Pentagon." Those were the big snow-walkers in Empire Strikes Back, in case you didn't know. And shame on you if you didn't.

Tell us what you think of the video in the comments section below. Any suggestions you have for future Viral Videos of the Week? Send them to me at [email protected] (Nothing naughty, folks!)