30 second exposure at f/5, ISO400 equivalent. The sky was nearly completely dark, so most of the illumination came from the sodium vapor lights at the nearby dock.
My favorite thing about the picture is how the long exposure smoothed out the waves on the water, making it look like a sheet of textured glass.
Click the image to see a full-size version (warning: large).
Here’s a 16 second exposure at f/8, taken a bit earlier. I like the invisible boat effect, and I like how the dock looks like it’s on fire.
In summary: a good tripod is worth its weight in gold.