You may have done some long exposure photos and perhaps a bit of street photography. But have you combined these two genres for long exposure street photography?
Consider this: Photographs are frozen slices of time, and your camera is a time machine capable of freezing or stretching a moment. A short shutter speed can freeze things that happen far too fast to see. With a long shutter duration, motion is blurred, stretching time. When photographing in busy urban environments where people, vehicles, and other things are on the move, long exposures can create a sense of motion in a static photograph.