By replacing the springs and shocks with air struts and adding a small computer and an air compressor, Bridgestone says its new Praxis system will let you ride comfortably to the track. Flick a switch inside the car, and the air struts lower the car and stiffen the suspension. Step out and adjust the dampers on each strut for track driving, and you're ready to hug the curves. The Praxis system is now available only for the Subaru WRX, popular with car customizers, but will be available on other cars starting next year. Driving: Couture in Las Vegas: A Fashion Show for Cars | 
