The wicked queen in Snow White had a magic mirror that told the truth. French scientists have gone one better. They have a mirror that will tell the ugly truth - five years on.
They have fashioned a thinking looking glass that will offer a reflection of the future, after years of binge drinking and junk food have taken their toll, according to New Scientist today. This mirror will know you better than you know yourself, and never fail to tell you so.
Researchers at Accenture Technology, in Sophia Antipolis near Nice, have devised a flat liquid crystal display television screen linked to a set of cameras and some powerful image processing technology. Its first role is to capture the real you, the one you present to the screen.
But the computer-powered mirror will also be picking up data from a network of discreet spy cameras around the house, which will monitor the time spent watching television, eating pizzas, drinking beer and paying sly visits to the fridge and the biscuit barrel. It will also ask - by vocal or text messages - to confirm the pattern of self-indulgence.
It will take the data, and a sophisticated software package will begin to assemble a picture of the likely effects of the day's diet and exercise, or gluttony and sloth. And then, at the touch of a button, it will reveal the future you, five years on.
One part of the programme will calculate the extra weight. Another will contemplate the ravages of time and dissolution on the face itself. Too much alcohol? The toll, five years on, will show up immediately in blotchy skin and early wrinkles.
The idea, of course, is to deliver a warning now: this is the digital mirror as personal trainer and nutritional coach.
"Technology can be quite persuasive," laboratory director Martin Illsey told the magazine.
"There will be several options for the visual feedback the user gets, ranging from weight gain to modifying skin tone, to increasing the shadows under the eyes."
A prototype could be ready this summer.