Flash Mobs are seemingly unplanned gatherings of large groups of people who converge in public (or semipublic) places for brief periods of time. All members of a Flash Mob simultaneously converge to form the mob and then quickly disperse again at a given time, everyone departing in different directions.
 
The first Flash Mobs took place in New York City; full details here.
 
Join this group if you'd like to be notified of future Flash Mob happenings worldwide.

For notifications about New York City flash mobs, e-mail themobproject@yahoo.com and ask them to add your address to their distribution list.

For discussions about and notifications of Flash Mobs specifically in the San Francisco area, see these Yahoo groups: sf-flashmobs and the_mob_project.

For Minneapolis flash mobs, see minneapolismob