All that I did was cut holes on the side of the case above the cpu and video card for 80mm fans in on vid out on cpu. the fans are what makes the noise if you want quiet get quiet fans (quiet fans generaly dont move as much air).
hmmn the inside? you mean fans? if you use your imagination, you can do a lot more. you can put a plexi glass window on the cover. make a rectangular hole and some plexi glass and rubber sidings. then you can put neon lights inside the case so that it'll show thru the window.
i've got 10 of my computers set up this way. it look great and it's an eye catcher.
A couple of good ideas already. I was thinking of putting fans on top blowing in and sucking out at the bottom. I will need to extend the case slightly on top and the bottom. I was also thinking of building 'air channels' inside the case so that you can have essentialy 2 big fans blowing and 2 extracting... Will attempt this as soon as my new box arrives....