When I've had to work late, my co-workers think I'm nuts riding at night. I feel safer in many ways - traffic is much lighter, the crazed commuters are off the road, and a good set of lights and rear reflector (required by state law) improves my visibility to drivers vs daytime. Biggest concern - any drunks are going to be "attracted the the flashing red light". Biggest problem - red lights that won't cycle because the road sensor won't react to anything smaller than a car (fixed by a recent change to the laws here on stop lights for bikes & motorcycles).