Took my D70 out the other night for some photography. These are straight from the camera with the except of the third one which was obviously converted to Sepia. C&C welcome!
Isn't nighttime photography great fun?
More so if you've got those nicely lit places that you apparently have got around you. I think I like the last one best, with the flag "frantically" waving and the water all soft due to the long exposure. I also think that one is best composed of all your photos here.
One thing you might want to try is a longer exposure on #2 or time it to get the street lights changing so in the photo the red, yellow, and green lights are all lit up at once. That's just a little thing I like about long exposure street photos.