There are about half a million bicycles in Amsterdam. While many are used by the inhabitants of this Dutch city, most of those half million bikes are parked, or chained, along the fences, poles, and lamp posts of the city. This gave me a chance to inspect them for modifications and street use mojo. I found a few that had taken your basic black single speed standard Amsterdam issue bike and altered the pattern with either a homemade paint job to make it easy to find, or else added a homemade basket to carry stuff.
Nice paint job! You can't miss this one in the crowd.
A kid's front seat made of wood and painted pink.
For carrying heavy loads and packages, how about a welded platform painted yellow?