I probably AVERAGE about 13.5 miles per hour. This is because my commute is in the city and I have to stop for traffic lights and traffic.

Also, I wear my work close when I bike, so I don't get gonzo enough on the ride to get too sweaty. I have to walk in looking fresh, smiling, and ready to hop right on the work.

Probably on the longer stretches, I hit 17 to 20 miles per hour or so depending on traffic and wind.