Toyota has created a piece of technology that can read drivers' moods and adjust the car accordingly.

It cannot, however, do anything about a Prius driver's chaotic internal combination of utter lassitude and glowing self-satisfaction.

Just a joke. The tech is a safety feature that senses the fettle a driver is in, based on facial recognition technology reading no less than 238 separate points. It then evaluates how he or she will react to a hazard and, if necessary, send out warnings.

According to a report in What Car?, Toyota has been working on the system for six years, based on the fact that a driver will behave differently depending on mood; an angry driver, or an upset one, is slower to detect and react to hazards than a happy one, Toyota's research suggests.

The company says that it's still around three years away from production yet - and it could be double that time before it's incorporated into vital safety functions.

However, it could come earlier for "non-vital" applications, like sensing when a driver is actually looking at the screen and turning it on on-demand, to save energy. Clever stuff.