What are the consequences of running an open case desktop computer with a regular fan to cool it down?

Emperor asked:


Wouldn’t a simple fan like this keep my computer running as cool as can be:

housewares.about.com/od/coolingproducts/gr/honsmllfan_RO.htm

What would be the consequences if any of doing this?I am assuming there would be more dust build up but that can be cleaned regularly.Is there anything other cons to be thought of?
I know there aren’t any consequences in the short run but what about in the long run?

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