I have been riding my bike to work almost exclusively lately. It is about a 23 mile round trip, which works out to around 45:00 each way, give or take. True, this doesn't compare favorably with the 25 minute ride in a car in the morning, and maybe 35 to 45:00 in the evening (don't ask me why, but it's definitely a longer drive in the evening.). But from an overall time perspective, the truth (for me at least) is that biking doesn't take all that much more time.
Car Commute:

Morning: Wake at 6:30, make coffee, shower, dress, eat breakfast, out the door at 8:00, arrive at work at ~ 8:30.
Evening: Leave office at 5:00, arrive home around 5:45.
Bike Commute:

Morning: Wake at 6:30, make coffee, eat breakfast, dress in bike duds, out the door at 7:30, arrive at building at ~ 8:15, shower, dress, arrive at office at 8:30.
Evening: Leave office at 5:00, change into fresh bike duds, leave building at 5:15, arrive home around 6:00, shower and dress.
So by commuting to work by bicycle, I'm getting two 45:00 cardio workouts each day, and I don't get up any earlier in the morning. I get home 15:00 later than when driving.
Honestly, before I rode to work for the first time two years ago, I thought it was impossible; especially since I'm expected to wear "Business Professional Attire" most days. But one day I just decided to give it a try, and now I'm loving riding past the Mobil & Exxon stations every morning and every afternoon!
BTY
http://This message has been edited by Better than yesterday (edited Jun-24-2007).