We've heard about cars that can communicate to each other for years. Each car knows what other cars are around it. They know when other cars are braking, when they're accelerating and when they're turning. And they use this knowledge to help ease traffic flow and reduce the chance of accidents.

Well I've just driven that car. It's a Volvo, and although the technology is a long way from production-ready, it's on the way.

It's clever stuff. For the demonstration, I drove an S80 equipped with GPS and wireless that allows it to communicate with any other car within a 300m radius.

We drove in a convoy of three cars, typical of any A-road gathering. The middle car, an XC90, effectively blocked my view of the lead car.

But when the lead car braked, I didn't need to see its glowing red lights to know it was slowing down. That's because Volvo's vehicle-to-vehicle communication system alerted me to it, and warned me. So I could prepare for a hazard that I couldn't see.