I know the airport card can be installed aftermarket because they sell them in the apple store. However bluetooth is only built in if you order it from the factory apparently. Otherwise you need an external usb adapter. Only problem is I have a printer/camera/ipod/isight/USB stick So I actually use the three USB ports and the two firewire. Could somebody tell me if a USB splitter would work, since the ports are all so close together, and whether or not it would be obtrusive? Thanks.