Over the past few years the concept of viral marketing has revolutionized marketing on the internet allowing marketers to expand the reach of their campaigns to an infinite number of people.There are several examples of these 'viral' campaigns beginning with the classic viral campaign by Hotmail. Most of us are familiar with the e-mail service that gave away free e-mail accounts to gain exposure. This free offer was ingenious, but it was not this aspect of their strategy that caused their campaign to go viral. The more effective aspect of the campaign in terms of it becoming viral was that each time they gave away a free account and that account holder sent out an e-mail message, there was an offer for a free e-mail account to the recipient of that e-mail also.