+1.

Like someone else mentioned, just make sure you have a light that has a wide spread. But even with a narrower spread, it'd be great to see how this works out.

Car headlights do not face entirely forward but instead face downwards to a certain angle illuminating the road surface. So if the driver is a fair distance away, having a light shining on the cyclist's reflective material is a great idea.

I once knew of a cyclist that had a 4 foot pole attached to his bike with a yellow flashing light on the top.