Dash-top satellite navigation looks flashy enough in car commercials, butthanks to clunky interfaces, cluttered onscreen maps, and obnoxious spoken prompts ("make an immediate U-turn!")it rarely lives up to the hype. Enter the TomTom Go, a polished new Dutch import about the size of a half-grapefruit. Suction-cup the Go to your windshield and enter a real-time video game starring you. The unit shows little else but the road ahead, plus labeled side streets, from an intuitive 3-D perspective. Need directions? In the time it takes for the light to change, you can input any address in the country by tapping on the touchscreen. From there, one of several optional voices (we prefer the librarianesque tones of "Lori") rides shotgun. Stray off course and Lori keeps her cool, effortlessly calculating alternate routes on the fly.