How do you do that light effect (i.e spelling out your name in a picture)?

I've seen a lot of my friends to this: http://i32.tinypic.com/27yopza.jpg





... How?

How do you do that light effect (i.e spelling out your name in a picture)?
Tripod.


Looong exposure (say 30 sec).


Dark room.


Light source such as a sparkler or a torch.
Reply:light time lapse long exposure line illusion


http://www.thinkcamera.com/news/article....





http://www.flickr.com/photos/burnblue/se...





http://digital-photography-school.com/bl...





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Reply:no idea if your friends are doing it ask them