The next two out of eight engines stated to fuel word of mouth are Tribalism and RSO explained as follows:
Tribalism: The desire to gather into tribes is fundamental to human nature. We like to associate with like-minded people, or simply to be close to people we find interesting.
RSO (Relevant Sensory Oddity): When our senses are presented with something extraordinary, we recognize an experience as special, and are subsequently more inclined to talk about it.
Cesvet, B., Babinski, T., and Alper, E. (2008). Conversational Capital: How to Create Stuff People Love to Talk About 1er éd. (FT Press).
Tony Babinski, Creative Director I Bertrand Cesvet, Chairman I Eric Alper, Lead Strategist [Sidlee]