What do you carry in the cabin of your car? And what do you need to be able to get at while you're driving it? Johnson Controls, a supplier of car interior modules, among other things, has done some research to find out.

It polled around 2000 drivers from Europe, the US and Japan. The number one item is not the mobile phone that you might expect, but sunglasses. Almost 40 per cent of the respondents considered a pair of sunglasses to be vital, presumably to dull a glaring sun or perhaps to make their owners look that little bit cooler.

The next four items were considered essential by just over a quarter of the sample apiece. Leading the trailing pack were mobile phones, which has you wondering how many are handling them on the move.

That portable sat-navs come third demonstrates that, while plenty of new cars have them as standard, there are millions of us still suckering TomToms and Garmins to windscreens; the fourth placed item was a drink bottle of some kind.