An hour of moving lights above and around Dodger Stadium, Los Angeles, California.
A composite from 995 exposures acquired over a one hour period. I've used 3-second exposures to catch the air traffic, a combination of longer and much shorter exposures (and some HDR) for the city and stadium.
I'm using a somewhat refined version of the technique I used in this shot.
Nikon D90, Sigma 18-50mm @ 27mm, f/4.5, ISO 200.