From Wired How-To Wiki

Nothing puts a damper on your holiday cheer more than being stuck in gridlock — less than a mile from the festivities, but hours away as far as those brake lights are concerned. Luckily, the days of waiting, wondering and wasting gas in traffic are over. A bevy of doohickeys and gizmos now exist to help us plot a shorter route to your grandmother’s house. Now if only an app existed to shorten your legs on a plane ride home.

Check Your GPS Device

If you’re lucky enough to have a Garmin nüvi or TomTom, both devices have free apps that monitor traffic conditions and update them automatically when you plot your route. Just wait for the green go-ahead signal before continuing on your way. Should you receive the dreaded red light, Garmin Traffic will even plot out alternate routes. Both devices gather their data from a variety of sources, including radio reports, cellphones and other devices currently on the road.

Check Your Phone

Don’t want to shell out an extra couple hundred bucks when you have a perfectly good mini-computer in your pocket? Smart. Apps like Waze and TrafficTweet provide real-time traffic reports on your iPhone. And if you don't want to surrender your mobility to the Apple Monster, Google Maps's Traffic View is still in beta. The plethora of apps available, however, does signal a significant flaw. The one thing that makes each app accurate is having as many data points — that is, users — as possible. Since there are so many different options, the data points are also widely scattered. This may change in time as users gather in one app versus another.

Pro tip: Make sure you’re stopped before you begin tapping away, or else hand the iPhone over to a passenger. Getting into an accident will certainly slow you down.

Seek Out City-Specific Information

Many larger cities collect traffic info for commuters. If you were heading through Boston during rush hour, or planning some other similarly foolhardy feat, this would be information that you’d do well to have. Smaller cities like Portland, Oregon, have a Twitter feed dedicated to monitoring local traffic (@pdxcommute), while larger ones like Los Angeles might have their own dedicated website. Websites like Traffic.com also provide up-to-the-minute information once you plug in your ZIP code.

Don't Add To The Mess

Tom Vanderbilt's enlightening 2008 book Traffic had a number of interesting solutions to ease the stress of traveling by car. A few unintuitive suggestions: Instead of speeding up and slowing down through patches of traffic on a highway, maintain a steady speed. When you see a sign for an impending lane merge, move into the next lane at the last possible point to utilize all available space.

Original article by Adrienne So, Wired.com.