Another Ghetto Fix is air conditioning filters. You can either buy a sheet of it or get a big square and cut it to fit. I would even look for the kind with thin metalk weaved in so that you can shape it and hook it onto things. I used this for the front of my computer behind the main bezel and for my fan intakes. Works so far and airflow is still good (load temps with only 2 intake fans is 42, idle is 30)