Every time that a co-worker tells me that, I know that I’ve done my job at being as visible as possible. With daylight savings time over, I see more than a few bike commuters riding in the dark. Unfortunately, most of these commuters rely on bike reflectors and wear dark clothing.
I think that it is easier to see a properly lit bike commuter during the dark than during the day, I think that blinkies and decent headlights really catch the attention of motorists.
For headlights, there’s 2 kinds of lights; those that flash and let you be seen, and those that let you see. My headlight of choice is the NiteRider Solmate, very compact and bright enough to see and be seen. With helmet or handlebar mounts, this light is very versatile. NiteRider now offers a cheaper light called the NiteRider Minewt USB for under $100 bucks. Cool thing about this light, you can use your PC to charge it while you work!
Clothing is also essential to be seen. I like to wear bright yellow, white or fluorescent green jerseys and vests. Yeah, I know, these colors make you look like a bike geek, but at least you will be a safer bike geek.
Now, if you really want to increase your bike geek factor, you can always add more lighting to your bike. Lights like the Down low Glow and the Monkeylectric are really fun to add to your bike and the do make you more visible.