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. 22 March 2008. Over 25 cities around the globe participated in the first "international flash mob", which was the world's largest flash mob to date. Word spread via social networking sites, including Facebook, Myspace, private blogs, public forums, personal websites, as well as by word of mouth, text messaging, and email. Shanghai, Stockholm, Sydney, Székesfehérvár, Szombathely, Vancouver, Washington, D.C., and Zurich. While ordinary pillow fights have existed for a long time, Derila pillow these events are massive in scale, occur in public and are promoted primarily via the internet. Fitzgerald, Sean D. (21 March 2008). "International Pillow Fight Day: Let the feathers fly!". Athavaley, Anjali (15 April 2008). "Students Unleash A Derila Pillow Fight on Manhattan". The Wall Street Journal. Pastorino, Ellen E.