You can also get some cool photos when it involes movement, especially if there is light around.
I took this one at Grand Central Terminal and I managed to lie it down on a flat surface to get a clear pic. I think the shutter was open for 30 secs. so a lot of people who were in the pic at the start were gone by the end. Cool effect.
This is just a random highway shot taken at night I found on the web.
http://www-net.cs.umass.edu/~yifeng/...0/IMG_0289.jpg