What is a kelong? How to build a kelong?

How did Groupon build its initial user base? What was their customer acquisition strategy?

• Answers do not have to be Groupon-specific.  What are some other examples of companies that have successfully combatted the struggles associated with creating a marketplace and facing the "chicken & the egg" problem (ie: bringing consumers and companies together simultaneously)

• Answer:

  Their initial customer acquisition strategy was largely viral.  As deals used to require a minimum number of buyers for them to "tip" and be activated.  As a result, early customers often evangelized deals to their friends to get things to tip.  That said, I'm pretty sure their initial strategy was simply more customers is better than less and it probably didn't get more specific than that as they were in hyper growth mode back then. More recently Groupon has used national deals - most notably - Starbucks.  As a way to acquire customers.  As its been well documented that Groupon likely loses money for every Starbucks deal sold.  Also of late, they seemed to be doing a lot more direct marketing (SEM, Display, and SEO) to drive purchases.