I did my first commute in the dark last night. I used the Planet Bike lights I bought a few years ago so I could ride in the park in the evening, and these were mostly adequate. Since I'm in NYC I don't really need them to see the road, just so I stand out. I don't know how many times I'll really do this though. It wasn't all that cold yesterday but I could see myself not wanting to have to get on the bike in the dark and the cold after a long day at the office. I figure I have maybe one or two more commutes in me this year. My alternate is the subway, so it isn't like I'd need to drive instead.