I live in Minneapolis and work in one of its suburbs (not a popular route to take in the morning). It takes me about 40 minutes to ride 6.3 miles to work. Last year, because of a knee problem, I had to take the bus for 17 days. Because of transfers and the associated layover times, and the less direct route the bus has to take (it can't go from my door to the office door), the bus trip (which costs four dollars for the round trip, by the way) takes...about 40 minutes.
Slightly off topic, gasoline here is $3.00 a gallon, which means that every day I ride to work I save half a gallon, or $1.50. I finally, this winter, have reached the point where I can go in all but the worst conditions, in comfort. As that capability has developed, I find that I am internalizing the concept of, why would anyone NOT use a bicycle to get to work? Why would I take the bus when it is no faster than a bike and costs $4.00 in addition? Why would I spend $1.50 (plus the hidden expense of wear and tear) for the privelege of hauling with me a piece of motorized heavy equipment which I then will have to store someplace while I am working? It's crazy to use anything BUT a bicycle to go that relatively short distance (unless other circumstances dictate, of course). And yet, when I walk into the office with the helmet and other stuff, there still are people who think I'M crazy.