I'm a strong (some would say fanatic) advocate of Environmental Justice, and began commuting by bicycle in 1991 because I was tired of polluting with an automobile just to get to work. Since then I've discovered that bike commuting is an excellent way to gain and maintain leg muscle strength, and sometimes helps with aerobic conditioning too. I also volunteer for the Cascade Bicycle Club's "Bike to Work Day" every year, even though I dropped out of the club because I'm putting my time and resources into other efforts.
One aspect of my commute that may interest others is that most of it actually occurs on a bus--I bike about 3.5 miles to a bus station, put my bike on the rack on the front of the bus, ride about 25 miles, and bike another 1.5 miles from another bus station to my office. The homeward ride is less on the bus and more on the bike because of the configuration of hills in the area. So, while I cover 60 miles a day, most of it is not on the bike!
I also use my bike for transportation to many of the community meetings and other activities--I consider bike use to be much more consistent with my values than driving an automobile, and am helping to create a world where we won't need mechanical aids so much in our lives, especially for travel. So I walk whenever an event is within a mile of home; it's even better exercise than biking!
I'm interested in riding technique and in a few gadgets. I was very happy when LED headlights became available.