I'm a bike nut. I work for a travel bike manufacturer (bikefriday.com), have been a bike messenger, and I've been a daily commuter for years.
I'm convinced that the bicycle is one of our greatest inventions and that it's true value has not yet been appreciated by the masses due to the pernicious nature of car culture (see "Divorce Your Car!" for more on that). I ride because I like it, but I really ride to encourage people to do so themselves.
Cars, on the other hand, are engineering disasters. Rarely have I seen a conservative design employed when making automobiles. There is so much material and dimensonal waste! This lack of moderation is exactly what makes the car such a horrid means of transportation in a population that is exploding from lack of factors that limit the population.
If we are to have a healthy environment and integrated community, an alternative to the car must be sought out.