The telephone book was once a familiar part of everyone's household. Some of the directories were big enough and heavy enough to be used as doorstoppers, but everybody would use them at some point to look up a neighbor's number or just check to make sure the phone company had listed their own name and address correctly. But the white pages directory of residential telephone numbers is another cultural artifact that will soon become obsolete, just as the buggy whip became unnecessary when Americans shifted from horses to automobiles as their favored form of transportation.