My commute is 40-50 minutes (depending mostly on the wind) each way. Add in about 10 minutes to change clothes and get the stuff on and off my bike. So between 1.5 and 2 hours a day. That's comparable to the time it would take by bus or shuttle.

The drive would be about an hour round trip. And that's only if I'm willing to pay $100 a month for parking. If I want to cut that to $40 a month, I won't save any time by driving either. Figure in the time cost of a 45 - 60 minute exercise program and I'm way ahead on time.

That said, I wouldn't want my ride to be much longer than it already is. (Especially in lousy weather!)