Cars, buses, taxis and trucks are all lethal threats to riders of bikes. Bicycles (and cyclists) might annoy or slow down people in cars. But I’ve never heard of a cyclist killing someone in a car.

So I’ve never quite understood the anger expressed from drivers towards bicyclists given this startling and bleak asymmetry.

Today, while riding down Market Street, I saw a silver Mercedes sedan sharply accelerate from the middle lane on Market and cut across the bike lane at high speed to make a right on to 10th before the light turned. He nearly took out the cyclist riding in front of me on the bike lane.

The driver was a middle aged man, Blackberry open. The rider in front of of me went up and tapped on the driver’s window. Even though I ride market every day, and see near collisions every day (mostly the fault of speeding, reckless drivers, not cyclists) this particular incident unnerved me. So I followed closely behind, and as the guy rolled down the window I said “Hey buddy, you nearly took out this guy.” Admittedly, I said this in a not-so-friendly tone.

The driver’s response was stunning. Instead of a sheepish “I’m sorry, really apologize” his response was a sarcastic: “Yeah, right.”

I couldn’t help but unload the F-Bomb at that point (the cyclist who was almost hit was much more polite, and he certainly would have handled it more diplomatically). The driver went into a state of rage — so interesting, again, given the asymmetry noted above — and said “You fucker, I’m going to get out of the car and punch you.” And then he hit the gas and made his right turn on to 10th.

He could have killed and injured — indeed, he almost did — that cyclist in front of me this morning. So why he got to angry as to threaten to punch someone in the face, that I just don’t get. After all, it wasn’t his life that was in jeopardy.

Plus today is the last Friday of the month, so it’s Critical Mass day here in San Francisco when bikers take to the streets, and remind folks there are other ways to get about the city than in cars.

Before I get to my biking bullet points, a quick look at my lovely ride (this one isn’t mine, just the model):

It’s a lovely Redline 925, an affordable single-speed steel-frame commuter, with a flip-flop hub if you prefer to ride fixie and quirky mustache handlebars. I’ve loved the commute on it, the simplicity of the bike and stiffness of the frame make it a blast to ride.

But riding in the city can be a drag, and here are some of the things I wanted to write down after a recent ride in to work:

1. Bikers Rule
One of the really delightful things about commuting by bike is the community of cyclists. It’s fun to chat with other bikers at the stoplights, admire their rigs and answer their questions about how I like the weird handlebars on the 925. Only occasionally do I encounter a rude cyclist on the commute (out riding with the spandex warriors on the weekend is a different story).

2. Pedestrians Rule, Too
It’s nice to ride into work, and see people walking to work. Corollary to point one above: the most offensive thing a cyclist can do is put a pedestrian in danger by riding on sidewalks, or blasting through cross-walks with people in them.

3. People who talk on phones and drive suck
I know there are lots of reasons people have to drive.  I own a car, we drive it, I get it. But there is no excuse for driving and talking on a phone. You might as well load up on a couple of sixers and a pint of gin. I see more stupid driving by folks on their cell phones than any other type (equalled only by people texting and driving).

4. Life is cheap
Riding your bike to work, you quickly learn just how cheap your life is.  One odd result of insurance is that people seem to be more careless in their driving, particularly towards pedestrians and bikers. Folks don’t think (much) about what they’d owe if they hit you, because they probably won’t have to bear the cost personally. More likely, they are thinking about the cost of being late to where they’re going, or the frustration of being stuck in traffic, the pleasure of rolling through the stop sign without a complete stop, the supposed convenience of being able to talk while they drive.

It’s those marginal benefits that measure the worth of your life in our world of cars and their drivers.