I recently started reading the classic environmental polemic Ecotopia written by Ernest Callenbach. Its got a lot of amazing ideas and innovative design techniques for urban centers. I'll get into those in longer posts later, but for now I'll just give a teaser related to bicycles.
"Ecotopians setting out to go more than a block or two usually pick up one of the sturdy white-painted bicycles that lie about the streets by the hundreds and are available free to all. Dispersed by the movements of citizens during the day and evening..."
15 hours ago