This morning as I left for the office, it was as dark as a total solar eclipse! I was glad to have an extra measure of visibility, in the form of headlight, taillight, and high-viz/reflective vest.
Far too often, when a motorcyclist or bicyclist is involved in a collision with a motorist, the car driver laments, "I just didn't see him!" Let's face it - our smaller vehicles are harder to see than that F350 pickup truck, or Wagon Queen Family Truckster. The problem is exacerbated by the dark. Don't be a victim!
Here's what I use - because it's cheap and apparently effective.
On the front, I have a single-AA battery LED flashlight. (I think mine cost about 8 bucks, 2 or 3 years ago. But they are very common nowadays, boasting lumen outputs from about 200 on up.) My model has a clicky-button on the back, that turns it off and on, and selects one of three modes - bright, dim, or strobe. I generally use the "strobe" setting when I'm riding down a familiar road and am mostly concerned about being seen by other roadway users. And when I'm on a less-familiar road, I choose bright, to light up my path. I use a rechargeable battery, and carry a spare battery with me. I attach the light to the handlebars with a little rubber-and-velcro doodad that I ordered with the light. (Both ordered from dx.com)
(I've got a bigger and far brighter light that I'll be trying out soon. Amazon made me an offer I couldn't refuse.)
On the back, I use a bright flashing red LED taillight. Mine is a Planet Bike Superflash. It was expensive by my standards - more than 20 bucks! But it's given me faithful service for 3 or 4 years, so it's money well spent. There are other cheaper-but-effective alternatives nowadays... we live during an LED Renaissance! The taillight uses two AAA batteries - I use rechargeables.
Stay safe, mis amigos.