In the Hoge Veluwe National Park in the middle of the Netherlands there are white bicycles that you can use for free within the park itself (which, of course, has an extensive cyclepath network). This reduces the number of cars and the need for hard infrastructure, and it keeps the park peaceful and visitors active.
It also seems to be popular; I had difficulty finding a parking space for my own bike at the Kröller Müller Museum in the afternoon, but when I left the racks were practically empty. As I cycled back through the exit at the end of the day, I found out where they had all migrated to:
Lancaster Dynamo Cycle Campaign 