Usability Views Article Details  home | timeline | recent | popular | e-reports | userati | about this site The Toughest Virus of All: Why viral marketing can never be a general purpose tool (11 Jul 2000) Article URL: http://www.shirky.com/writings/toughest_virus.html Read 99 more articles from Clay Shirky sorted by date, popularity, or title. Next Article: What will people pay for? This site is a labour of love built by Chris McEvoy