Shutter Drag (Night)

Set your shutter to 1/15 or slower. ISO low (400 or under). Aperture to taste - f/5.6 is a reasonable start. Fire the flash. The flash freezes your subject. The slow shutter drags the ambient light - headlights, neon, street lamps - into streaks behind them.

Hand-hold deliberately. A small amount of camera movement adds to the effect. Too much and you lose your subject entirely.

Watch for: light sources in the background - the more the better. Moving traffic. Wet streets double everything.

The point: still subject, chaotic world. It's a good metaphor and it looks brilliant.