If you thought Audi's retina-burning headlights were just good for clearing slower traffic out your lane, then think again.

According to the European Commision, they're also a bona fide fuel-saving technology, too.

Official tests compared Audi vehicles fitted with the all-LED technology to more conventional halogen counterparts. Not only were the LED units considerably brighter, but they also saved a small but measurable amount of fuel.

The improvement amounts to a 1.6 gram CO2 saving every mile. It may not sound much, but it adds up over the course of ownership.

The extra efficiency stems from the reduction in power needed to illuminate LED lights.

A typical halogen light on a low beam setting can consume 135 watts of power. An LED unit on the same setting only draws 80 watts. That extra power needs to come from somewhere, and that somewhere is your engine--extra electrical load on the alternator means an engine working ever so slightly--but measurably--harder.

Not that Audi developed its headlights solely to save gas, but it's a happy side-effect.

The real benefit is extra illumination in night driving, offering considerable safety benefits. Audi says its headlights have a color temperature of 5,500 Kelvin, similar to daylight. Not only can you see further up the road thanks to the precise beam patterns possible with LED technology, but it's easier on the eyes, too.

Audi's all-LED headlamps debuted on the 2008 Audi R8 supercar, and have since appeared on the A8 luxury sedan (with 76 LEDs per headlamp unit), the A6, the A7 Sportback and the new A3.

The multi-LED units allow Audi to control beam patterns with much more accuracy, enabling high-tech features like beam adjustment according to the road you're driving on, based on satellite navigation data.

And, yes, they're great for encouraging people out of your way on the freeway...