It's not the sexist part of a modern, efficient vehicle, but anti-idling tech is pretty darn useful. The Automotive Researchers' and Journalists' Conference of Japan (RJC) thinks so, and has picked Mazda's i-stop as its Technology of the Year for 2009. I-stop is a system that shuts down the engine when the car has stopped, much like the Stop&Start Micro-Hybrid system (which won the 2008 Automechanika Innovation Award) found in Daimler cars, Audi's start stop system, Fiat's start stop system, and, oh you get the picture. Everyone's doing it.
I-stop is pretty fast, able to restart the engine about a third of a second, and Mazda says it reduces fuel consumption by about 15 percent in a vehicle like the Mazda3 (aka Mazda Axela). In 2007, RJC picked Volkswagen's TSI engine technology as the Technology of the Year.