There is no set formula to make viral marketing successful. Rather, it depends on the situation. It worked with Paypal because customers were able to transfer money to non-customers, therefore growing the network quickly.

1. 
   Lecture 1: Lucky or Brilliant?
   
2. 
   Lecture 2: Paypal Cofounders Met in Terman at a Seminar
   
3. 
   Lecture 3: How We Attracted Our First People
   
4. 
   Lecture 4: Selling Employees, Selling Investors, and Selling Customers
   
5. 
   Lecture 5: Selling Investors: Beaming at Bucks
   
6. 
   Lecture 6: Selling Customers -- Getting the Product Out
   
7. 
   Lecture 7: Exponential Growth
   
8. 
   Lecture 8: Coping with Fraud
   
9. 
   Lecture 9: The Initial Public Offering (IPO)
   
10. 
    Lecture 10: Viral Marketing
    
11. 
    Lecture 11: Changing the Business Model
    
12. 
    Lecture 12: Beating Competitors - and the Conventional Wisdom
    
13. 
    Lecture 13: Negotiating with eBay
    
14. 
    Lecture 14: Advice to eBay (the acquirer)
    
15. 
    Lecture 15: When and Why to Merge With a Competitor to Dominate a Market
    
16. 
    Lecture 16: Paypal is Not a Bank
    
17. 
    Lecture 17: Looking Ahead to Their Next Venture