The Spy Video Car uses 12 AA batteries and goes for $140 direct from Wild Planet, but it's available at Target and Toys R Us for $99 during the month of December. It's the perfect gift for the little spy on your holiday list.

-- Mike Elgan

Most useful USB-powered gadget: USB Roll-Up Piano

Brando's USB Roll-Up Piano plugs into your PC, turning it into an electronic piano and synthesizer. The 49-key piano keyboard is 29 in. by 7 in., plus a control unit that's 8.5 by 3.5 by 1.25 in. Roll it up and stuff it in your pocket. Let's see you do that with a Steinway.

The $46 piano features 136 instruments (eight of them percussion), six tones, 100 prerecorded rhythms, a built-in metronome and even tone effects such as vibrato and portamento. You can record what you play and use the piano software's learning mode to practice. All programming and sounds are activated with the Windows XP-only software. Power comes through the USB cable -- no batteries required.