One definition of a commodity is something that you take for granted. I'll bet there aren't many readers out there who wake in the morning and exclaim, 'Thank goodness there's air in the room to breathe!' Likewise, computer users will seldom give thanks for their operating systems, a proclamation like 'praise be to those at AT&T and BSD for giving me Unix!' would likely raise more eyebrows than nods around an average water cooler.