specific cause. Then he thought of her and her “very small” foundation. Jeanette told me she texted back, “You must be joking,” but eventually she did it. Then she nominated her close friends in Pelham. They nominated their friends, who did the same. And so on – a ripple effect from a few local townspeople, to the whole community, to neighbouring towns, and finally, a tidal wave on Facebook. The giant of social networks isn’t a nebulous universe of strangers, but a web of communities where compelling content and ideas can quickly become a pandemic. Within weeks, Facebook’s CEO, Mark Zuckerberg, had taken the ALS Ice Bucket Challenge (nominated by New Jersey Governor Chris Christie), alongside other celebrities such as Justin Timberlake, David Beckham and Justin Bieber, whose video gained over one million likes alone. Likes turned into donations. In just one month, the ALS Association in the US received almost $100 million, dwarfing the $2.7m donated over the same period the year before. Awareness soared as over 2 million videos and 4.5 million Twitter mentions saturated social and traditional media. Searches for information about ALS increased dramatically; the ALS Wikipedia page received 2.7 million views that August, compared to only 1.6 million in the preceding 12 months.