Well, I am note sure how scalable this idea is but a new trend is emerging in European Cities, Cargo Cycles! You read correctly. Bicycles that haul cargo performing deliveries in cities. While this may seem unlikely at first glance, Consider that many light delivery trucks can cost 60 cents per mile to operate, before payroll of the driver! Further, in a busy city bicyclists often can move through and around traffic much mode efficiently than a truck. While I do not speak, it was pretty clear to me how to read the Cargo Cycle Database that shows the different styles of cycles.
I know, it seems weird. So did the concept of of tablet computers decimating the laptop market just 5 years ago. Perhaps cargo cycles doing deliveries in the city is the next big thing in the US!