Anyone who rides at night needs BOTH reflectors AND lights.This tail light from Amazon comes well recommended for the price and has nice vintage style. I'd like to see if I could mount it on my fender, to add to the blinkie I have on my helmet. We will just have to work out how to secure the lens which apparently has a tendency to fall off.
For a more futuristic look, this other light from Amazon has an interesting look. I could see it on a bike with a more modernistic aesthetic. It almost looks Star Trek to me, and I like that about it. It is also nice in that it appears to mount with hardware. I suspect you leave it on the bike and that makes it hard to steal. Anything that makes your commute simpler is always a good choice.