You know what we hate? Sitting in gridlock when we could be, you know, out doin' stuff. At the very least, it's the antithesis of the "wind in your hair," Dean Moriarty-esque image we've carefully cultivated over the years. "If only," we say to ourselves, "there was a way to find routes that were free of congestion." Sure, we've heard all about your fancy real-time traffic updates -- but how well do they actually work? According to a study by the GIS data and services company NAVTEQ (so, you know, take it with a grain of salt), drivers that use GPS systems with real-time traffic info spend 18% less time behind the wheel than those who do not (that's a whopping four days over the course of a single year, or enough time to watch 1 1/2 Peter Watkins films). In addition, the company says that smarter navigation has been shown to lower CO2 output by 21 percent -- which is a good deal, no matter how you slice it. There's been no study yet to determine how drastically driver performance would decrease if Bob Dylan was the voice of your PND, but we'll definitely keep our eyes out for that one.