Electronic spaces unhinge a crowd of visitors: They can appear in a flash and then leave in a flash. During the chess match between Deep Blue and Gary Kasparov, the IBM web site welcomed 5 million visitors. When the match was over the site was empty. On the eve of the 1996 U.S. elections, the CNN web site experienced 50 million attempts to log on. The next day, the crowd was gone. One day a flash crowd is pounding at the doors, the next day they have vanished. The mass audience has transformed itself into a wave that swishes around from one hot spot to another. But the nature of spaces is that in order to accommodate a flash crowd when they do come, you have to be ready, tooled up.