Internet referral services, hosted either by independent third-party infomediaries or by manufacturers serve as ``lead-generators'' in electronic marketplaces, directing consumer traffic to particular retailers. The conventional wisdom on Internet referral services is that they are valuable to...

We review research on revenue models used by online firms who offer digital goods. Such goods are non-rival, have near zero marginal cost of production and distribution, low marginal cost of consumer search, and low transaction costs. Additionally, firms can easily observe and measure consumer...