Electronic publishing may mean no more ink under the fingernails, but some things never change: publishing is still highly speculative. 18th century publishers used pre-publication subscriptions to help them choose projects and plan print runs. We'll look at how a modern e-publisher reinvented this model for the web to ensure that every project is profitable. We'll also examine a real-world example of letting users transparently establish the price/demand curve, all with real data from a 7,000 title e-publisher.