Maybach, maker of some of the world's best limos, has solved the problem of sunroofs letting in too much sun on a hot day: make the opacity of the glass adjustable.

The view of the adjustable sunroof from inside the Maybach 62. Its opaque screens look a little like a Japanese-style room divider.

This feature is purely aesthetic, and subtle. The front end of Aston Martins have no lateral seams across the bonnet our around the headlights, giving the cars a uniquely light, fast look.

In the rear-view mirror, Aston Martins have a pleasingly intimidating look.

Here's a safety feature that improves the driving experience - intelligent headlights. A sensor on the windscreen of certain new Mercedes models detects where oncoming traffic is and dips the headlights accordingly, allowing the driver to focus on driving and maybe listening to music instead.

Another Mercedes idea: the 'Airscarf' blows hot air onto the neck of the driver and passenger so they can cruise around with the top down during the colder months. Also available in the Audi A5.

The Mercedes S-Class is best known for its many safety innovations, but the latest model is the first with a split screen in the dash, which simultaneously shows a movie or TV for the passenger and navigator for the driver.

This is how the screen on the Mercedes S-Class dash looks from the two perspectives. This feature will also be available in the Jaguar XJ next year.

The layout of the Lexus LS600h looks as comfy as any other limo. Until...

You press a button on the rear console, the passenger's seat slides forward, one of the back seats reclines and a foot rest appears. Business-class comfort for the road. Also available in the Maybach 62.