A design competition entry from a few months back, Light Lane was taken seriously by Boston based Altitude Inc and is now in the early stages of production. Mounted on the back of your saddle pole like a regular led light (infact it is a regular led light aswell), two laser beams are projected down on the ground to your side clearly marking your space so nobody gets all up in your grill. Can see this being very handy on the Dublin daily dabble with suicide that is cycling home from work in the autumn/winter.
More info on it can be found on the Light Lane page
Via Cool Hunting