Be the side(s) in your multi-sided market

Anyone who's tried to start a multi-sided market business (the most common being a two-sided marketplace, like eBay, with buyers and sellers) knows one of the first major challenges is the chicken-and-egg problem. In order to attract sellers, you need buyers, but in order to attract buyers, you need sellers. On a dating service, the two sides are obvious. And so on.

How to get out of this infinite loop of emptiness? Kickstart things by being one or more of the sides in your multi-sided market. In other words, fake it til you make it.

Seeding and Weeding
 
Dating services simulate initial traction by creating fake profiles and conversations. Users who come to the site see some activity and are incentivized to stay on. Marketplace sites may also show fake activity to attract buyers and sellers.
 
Seeding Demand
 
In the book, Paypal Wars, Eric M. Jackson talks about how PayPal grew a base of sellers who accepted PayPal by creating demand for the service among buyers. When Paypal figured that eBay was their key distribution platform, they came up with an ingenious plan to simulate demand. They created a bot that bought goods on eBay and then, insisted on paying for it using PayPal. Not only did sellers come to know about the service, they rushed onto it as it already seemed to be getting popular. The fact that it was way better than every other payment mechanism on eBay only helped repeated usage.
 

Other great war stories and tips within.