My favorite picture from today is a picture of a rose taken at night.
To tell the truth, the reason this is my favorite picture is that I neglected to use my camera until dusk fell and wasn't happy with my pictures. So, I went outside and played with my camera and my flash in the dark.
Night photography is such a challenge. For one, the flash has to be pointing straight at the subject and since I'm not using a flash diffuser or bouncing a flash off the ceiling like I would during the day, my straight on flash produces flat light. Secondly, it's hard to see if your subject is in focus.
Use a good lens, give your eyes time to adjust, check your images, and take lots of shots - that's my advice (not that I am an expert on this subject). Also, when taking a picture at night make sure there isn't anything in flash range behind your subject and you'll be doing good. Anyhow...this is a subject I want to learn more about, but tonight I gave it a shot.
30D, ISO 1250, f4.0, 1/60th of a second, 70mm of 70-200L, 430EX Speedlight set to H (high-speed sync), some editing in Photoshop