The Stelarc "Walking Head Robot" pretty much is exactly that : Tech Digest

Two metres across. Six metal legs. A blank humanoid face with cold, unfeeling black eyes. Tubes. Pistons. If you've ever had a nightmare about a robot from the future tracking you down because of what your children will do several years from now, chances are it looked a bit like one of these.

The Stelarc creation uses ultrasound to minimise the embarrassment most robots face of bumping endlessly into walls, the "head" LCD screen rotates to look at any human in the vicinity, and it will, one day, be able to talk to you. If only to ask you to confirm your name before it blasts your brains out.

Quite nice, but not quite as impressive as BIG DOG. BIG DOG will CRUSH ALL.

(Via GW)