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ost_uid0="VampireNinja"]makes the BG and pic look "dirty"..[/quote]
The style is formally known as "grunge" it's not a hard technique to pick up on, as its basically a way of making your work look old, and usually quite random and crappy. It's good for bigger pieces of work that would usually have a meaning.
Bad choice of imagery with the technique you want to use..
A good idea of imagery for grunge would be; a frale old woman, or a dieing flower.