Flash Crowd

Flash Crowd was the title of a 1973 short story by the science fiction
author Larry Niven, one of a series about the consequences of instantaneous,
practically free teleportation booths that could take one anywhere on Earth
in milliseconds.

One consequence, not predicted by the builders of the system, was that with
the almost instantaneous reporting of newsworthy events, tens of thousands
of people worldwide would flock to the scene of anything interesting-- along
with criminals, hoping to exploit the instant disorder and confusion so created.

On the World Wide Web, a similar phenomenon can occur, when some web site
catches the attention of a large number of people, and gets an unexpected
and overloading surge of traffic: a notorious example is the Slashdot effect.

Another similar phenomenon is the Flash mob.