I used to ride for JJs too! I was one of the only women who did it for more than a few blocks, and at the Arizona store I was the only person to deliver only by bike (car got totaled...). It is a great workout, great fun, and excellent money if you get the right shifts. In AZ I would average 20 - 40 miles a day, in 0 - 6 mile sprints. When they still tracked delivery drivers by average delivery time, I was always among the top drivers because biking was so much faster in traffic.
My current job occasionally involves traveling offsite for meetings. My employer keeps a few beaters in fair working condition, but none of them fit me. I just make sure to ride to work that day if I want to ride.