This is the culmination of 92 shots, taken from an open window in my bedroom. Each shot was 15s, f8, ISO 200 at 28mm. I learned three things with this image:
1) Take JPEGs, not RAW, unless you can record images straight to a computer. Even a 2-4G card isn't enough for what I wanted.
2) Make sure the camera is actually taking pictures before you leave the room. You could come back two hours later to find it only took one picture.
3) I had no idea I could see so many stars in the city. To the naked eye, I saw maybe 3 of these stars.