IT IS A great undertaking, a marvel of organization and enterprise involving dozens of corporate executives, scores of individual entrepreneurs and thousands of workers. In the end not a single widget is produced, and yet there are millions of dollars in the till. This is the miracle of the "thon," as exemplified by last Saturday's 16-hour "Live Aid" rock concert to benefit African relief.

"Thons" are a means of raising money for good causes and seem to be based on the theory that great effort inevitably brings forth great wealth, or at least it should. Thus people organize themselves and do something -- just about anything legal but not too boring -- for stupendous lengths of time while the pledges pour in to whatever charity they are knocking themselves out for. There are dance- a-thons, sing-a-thons, telethons, radiothons, bike- a-thons dial-a-thons, talkathons. At one college, students will keep a basketball game going for an entire weekend to fight a disease; at another they will push a peanut around the campus perimeter with their noses to benefit the fresh-air fund.

Saturday's was an international "thon" of monster size, witnessed, according to some estimates, by well over a billion people. The air was sometimes a bit thick with self-congratulation, as it often is when entertainers exert themselves for charity, and the music wasn't always the greatest. Some who commented on it seemed to think the important thing was whether another milestone in the youth culture -- another Woodstock -- occurred.

But of course that wasn't the important thing. What mattered was how many millions of dollars were raised, and in that regard "Live Aid" seems to have done well by the hungry people of Africa -- about as well as a number of national governments have. Governments are less interesting to watch as they go about raising money for disaster relief. On the other hand, they'll still be there making the next payments after the music has ended.