And what a wonder of mixed-signal technology it is. The Aibo has some 20 motorized joints, which allow it to mimic a dog walking, sitting, lying down, flapping its ears and wagging its tail. It has a built-in stereo microphone and will learn and respond to about 50 voice commands. A stereo amplifier and speaker allow it to respond with a variety of its own tonal sounds.

There's a couple of technology trends that make this $1,500 plaything possible (as well as its lower-priced imitators). One is the trend toward pairing high-resolution data converters with the inexpensive processors used to control the elbow joints-often on the same chip. I don't know whether the Aibo uses any of these, but companies like Analog Devices have paired 12- and even 16-bit A/D converters with 8051 8-bit microcontrollers. The data is "folded," that is, taken in by the microprocessor in two mouthfuls.

The object here is not processing speed but precision. In rotational positional controllers, the 12-bit data converter slices the rotational arc of an elbow joint to one part in 4096-the same kind of control implemented for many hundreds of dollars by Cincinnati Milacron in its industrial robot line. Microchip Technologies has similarly added 10- and 12-bit converters to its popular PIC series controllers, and National Semiconductor has added a 10-bit device to its Cops family.

The other trend is better voice recognition devices, at least for command and control applications: "Sit, roll over, shake hands," and, for a tail wag, "good doggie." Companies like Winbond, Sensory and Frontier Design have gotten very clever at increasing the usable vocabulary of those devices without increasing their memory cost.

I would say Robodoggie has a bright future, but for certain all-too-anthropomorphic flaws: Could you count on him to growl at your enemies? or park himself affectionately at the feet of someone you'd like to meet?

Ah well, I wish you all better luck at getting your Christmas wishes fulfilled, and smooth sailing into next year's choppy waters.