In a conversation (you guessed it ... in a pub) over Christmas a friend mentioned that there had been a recent development in crash helmet technology. The development projected an image of what was behind you onto you your visor by way of a

series of periscope type mirrors

running through the helmet.
Am I the first (and probably biggest) sucker of 2006 or has anyone else heard of this ? I suspect I was the unwitting recipient of the first wind up of the year. If such a device exists does anyone have any details - manufacturer, cost, distributor, experience of using one, etc, etc.
If this is pure fantasy then please ignore this thread and I will skulk off into obscurity for being so easily taken in !!
Happy New Year everyone.
Jiminy