This is a self powered laser light, the battery that is recharged via a dynamo and this is what it does …
The laser draws an ellipse of light that is sensitive to anything crossing the perimeter. If a car comes too close, the light becomes red and all the horns will go off – until the car moves away.
As the article states you can’t rely on “standard-fare reflectors that may or may not reflect properly, depending on the angle of the car headlights hitting you”. So I agree that anything that could help you to be seen on the road at night is a good idea.
Though looking at the drawings this very visible ellipse it is very close to the bicycle and if it only turns red when a vehicle that close to the bicycle. Then that vehicle is way to close to the bicycle already and can’t see the light anyway because it is beamed to the floor. And also this thing will go on and off all the time if you are living and cycling within a busy city like London. Other cyclist, pedestrians and cars are that close to you pretty much already. And what is going to happen if you pass a lamp post or other street furniture.
Hmm, hock it up with a sound system and a few other bike rides and you have a moving disco :)