A pillow fight flash mob is a social phenomenon of flash mobbing and shares many characteristics of a culture jam. The flash mob version of massive pillow fights is distinguished by the fact that nearly all of the promotion is Internet-based. These events occur around the world, some taking the name Pillow Fight Club, a reference to Fight Club by Chuck Palahniuk in which anyone could join and fight as long as they fought by the rules. Both the London and Vancouver Pillow Fight Club's rules reflect that described in the book and feature film.
The trend owes much to uses of modern communications technologies, including decentralised personal networking, known as smartmobbing. Word of the events spreads primarily via digital means, usually on the internet via email, chat rooms and text messaging which result in seemingly spontaneous mass gatherings. Pillows are sometimes hidden and at the exact pre-arranged time or the sound of a whistle, the pillow fighters pull out their pillows and commence pillow fighting. The pillow fights can last from a few minutes to several hours.