@lorddef:
Drill plenty of holes on both shortsides and mount it standing up on a wall or something with one shortside up and one down with nothing directly above or beneath it. The circuits inside it will then warm the air inside the case and make it rise up through the holes in the shortside facing up, forcing fresh cold air to enter the shortside facing down. This method of cooling is called convection cooling and should be enough for this case.
/Patrik
