This Active Trans video is one of the best illustrations of how hard it is to see cyclists without lights (Bike Ninjas). With the time change, it's incredibly important to have your bike ready with lights.
Buying lights: Your favorite local bike shops will have a range to choose from. You'll need a white headlight and red taillight, sometimes they come in sets. There is always the online option as well:
Next level: I also like to go next level and wear high-vis clothing. Rapha has a sale right now on their new high-vis line. I own the high-vis vest in pink and you can literally see me coming from 2-3 blocks away.
Rapha High-Visibility Collection, "Night Moves"
Another article about staying visible when it's dark outside. This one gets a little more into the science of being visible to motorists:
Thanks for sharing this - good article - worth reading.
Good article. Maybe a strip of something reflective clipped around each knee would be useful.
Here's an Infographic we did on Illinois law regarding bicycle lights.
I did a Google search and really didn't come up with an easy lumen to distance chart to help but in a light description for Knog, I found this, "Front LED generates 20 lumens for 500+ meters; Rear LED generates 11 lumens for 500+ meters of visibility"
500 meters is about 1640 feet.
You can also use the rear light instead of a rear reflector (both would be great but if you don't already have a rear reflector, this is a good option). Here's the ordinance:
9-52-080. Head lamps, reflectors and brakes. (a) Every bicycle when in use at nighttime shall be equipped with a head lamp which shall emit a white light visible from a minimum distance of 500 feet from the front and with a rear red reflector capable of reflecting the head lamp beams of an approaching motor vehicle back to the operator of such vehicle at distances up to 200 feet OR a rear lamp emitting a red light visible from a distance of at least 200 feet from the rear.
Here's a twinpack on Amazon (has both front and back lights) for under $40:
We also have a thread from earlier this fall in which fellow Chainlinkers shared what they like to use for lights:
It's still surprising to me how so many cyclists with no lights still exist. Last night riding home from work in the snow storm, I passed a cyclist with no lights who had stopped under a viaduct for a brief reprieve and to wipe off his glasses and casually said, "Get some lights," as I passed him. He caught up to me later while stopped at a red light. He leaned over and asked defensively, "Do you take it that personally that I'm riding with no lights?" I told him that while doesn't personally offend me, I can't see him at all out on the road. He turned left and that was the end of our interaction.
As I rode the rest of the way home getting pelted by snow, I thought about his question. As a nurse, it is my job (and my nature) to care for people, and I naturally think that everyone should have head and tail lights so they can be seen. Riding without lights, though illegal, is his choice, but if that choice were to contribute to him getting in an accident, it would be quite personal when I am the one caring for him on the ground. It's frustrating that common sense isn't so common.
As for light preferences, I'm partial to Knog's USB rechargeable lineup. I use the Blinder Road 2 and Road R, but pretty much all of their lights are bright enough to be seen in the city.
I used to use the Knog hipster cysts as supplementary lighting. They're quite bright for being so small, and it's easy to wrap one or two on the handlebars or seat post. But I didn't always remember to take them off when I went inside a store for a few minutes, so most of mine have been stolen. Although I don't like being the victim of theft, if somebody got home safely because they took my lights, well, I don't feel quite so bad about it. But I can't afford to donate any more of these to the ninjas, so I won't buy them again.
A cycling "ninja" is a hazard not only to himself (frankly, I don't give a rat's ass for moron's opinion or even if he ends up dead and earns the Darwin Award), but to other cyclists most of all (see Tom's comment above).
By the way, I would give (and have given many times) a piece of mind to a moron driver or a pedestrian. A moron is a moron is a moron, regardless of its mode of transportation.
Speaking of lights and drivers: I've warned quite a few cabbies about their headlights being off after dark, and every time they thank me. Because why? Probably they might be actually stopped by a police and fined for that—unlike us cyclists. As someone's said here, unenforced law is ignored.