In reply to Martin W:
I have a very bright rear light under the saddle, a lesser one on the seat post and another on my helmet. I wear a runner's reflective tabard. On the front I have two very, very bright lights - in areas with street lights they flash to a different rythym. I also have a spare tiny flashing light for cold weather premature battery
failure.
Each wrist has a reflective and flashing armband - for side visibility, turn signals and visibility to drivers who half-overtake and then forget you're there.
Reflective bands on ankles.
My commuter bike has reflective tape all over it and a third low front light on the offside fork, another light on the pannier (4 on the back in total) and a pannier with a hump cover on it. That bike also has dayglo yellow wheels.
I am a moving Christmas tree, but I am but nothing in comparison to one guy who works here - he has a full son et lumiere - stereo, LED light show, the works - serioulsy impressive stuff, but not lightweight