This media darling looks like a cold mechanical killer out of a sci-fi, shoot-'em-up video game, but when you turn him on, his brusque brand of charm melts through. I took Robosapien to Boston over Thanksgiving, and every single member of the extended family—with the exception of a certain West Highland terrier named Cappuccino—now feels the way I do.

Press the button on his back, and Robosapien yawns, stretches and then awaits commands. You can drive him like a remote-control toy—he gets around pretty quickly on most surfaces, though shag carpets and the slickest wood flooring break his stride. Aside from standard movements of his arms and legs, he's got many slick moves, accompanied by unintelligible phrases the makers claim is bona fide Caveman. Some moves, like Sweep, Strike and Bulldozer, are meant to intimidate; others, including Whistle, High 5 and Burp, show off his persona. There's even a Roar—Robosapien's take on Walt Whitman's "barbaric yawp"—that does both. Preprogrammed strings of moves include a kung-fu demonstration, a showcase of his "attitude" and a hilarious dance routine, complete with music, that never seems to get old. When neglected, he stretches, snores once then waits, staring at you with beady little red glowing eyes.

Part of the Robosapien allure is simplicity. Anyone who's ever seen a remote control is able to drive him around, and within a few minutes can manage his trickier commands. Though he's not very good at picking things up, and kind of lousy at throwing anything that does end up in his hands, most people tend not to notice, since it's easy to get him to do so many other things.

The other side of the attraction is that Robosapien is really not simple at all, as anyone who goes back to read the manual can discover. His body is covered with touch sensors (buttons, really) that can be programmed to trigger six-movement series that you plan out. You can also build a master program with 14 steps, and each step can be one of those six-move sensor programs, making it possible to do some lengthy custom routines. You can even pull suggested programs from the Robosapien website. Sadly, once you turn off the Robosapien, he won't remember any of the programs—I hope the next version will come with a bit of onboard memory.

Since Robosapien was designed by a robotics physicist, who through his work at Los Alamos National Laboratory has contributed to NASA and various Department of Defense projects, it's sort of expected that people will try to hack it. Google "Robosapien hacks" and plenty of sites pop up—people are already mounting cameras and other cyber stuff on their own Robosapiens. The word is that the makers themselves encourage the inquisitive nature (though once hacked, a Robosapien's warranty is voided).

The point is, Robosapien is hot because it will impress practically anybody, from a six-year-old rug rat to a sixty-year-old comp-sci professor. Pre-Christmas gift hype is one thing, but fully programmable dancing kung-fu robots that pass gas? Well that's another thing altogether.